To reproduce:

public Form1()
{
    InitializeComponent(); 

    this.radScheduler1.Appointments.Add(new Appointment(DateTime.Today.AddHours(1),TimeSpan.FromHours(3),"Meeting"));
    this.radScheduler1.ActiveViewType = SchedulerViewType.Week;
    this.radScheduler1.GetWeekView().RangeFactor = ScaleRange.HalfHour;
    this.radScheduler1.SchedulerElement.DragDropBehavior.AutoScrollDayViewOnDrag = true;
    this.Size = new Size(800, 350);
}

It's necessary to stretch down the application so that a few hours are shown (let's say 4 hours) and the appointment is a bit less, for example 3 hours. If you look at the gif, I am scrolling down around 14, then I'm stopping a bit, while always keeping the mouse button pressed, and then I start scrolling up: at that time the scroll results in going down until 19, instead of going up.

Workaround:
 this.radScheduler1.SchedulerElement.DragDropBehavior = new CustomAppointmentDraggingBehavior(this.radScheduler1.SchedulerElement);

public class CustomAppointmentDraggingBehavior : AppointmentDraggingBehavior
{ 
    public CustomAppointmentDraggingBehavior(SchedulerVisualElement activeOwner) : base(activeOwner)
    {
    }

    protected override void HandleMouseMove(Point mousePos)
    {
     
        base.HandleMouseMove(mousePos);
        
        DayViewAppointmentsTable table = this.ActiveOwner.Scheduler.DragDropBehavior.ActiveOwner as DayViewAppointmentsTable;

        if (table != null && this.ActiveOwner.Scheduler.DragDropBehavior.AutoScrollDayViewOnDrag)
        {
            Point pt = table.PointFromScreen(Control.MousePosition);
            FieldInfo fi = typeof(DayViewAppointmentsTable).GetField("lastMovingPoint", System.Reflection.BindingFlags.NonPublic 
                | System.Reflection.BindingFlags.Instance);
            fi.SetValue(table, pt);
        }
    }
}

Note: If you open the context menu over a recurring  appointment and select "Edit Appointment", when the EditAppointmentDialogis shown, the EditRecurrenceDialog is shown as well. But when the EditAppointmentDialog is shown by double clicking, the EditRecurrenceDialog  is not opened at all.

Workaround:
 this.radScheduler1.SchedulerInputBehavior = new CustomBehavior(this.radScheduler1);

public class CustomBehavior : SchedulerInputBehavior
{ 
    public CustomBehavior(RadScheduler scheduler) : base(scheduler)
    {
    }

    public override bool HandleAppointmentElementDoubleClick(object sender, EventArgs args)
    {
        MouseEventArgs mouseArgs = args as MouseEventArgs;
        if (mouseArgs == null || mouseArgs.Button != MouseButtons.Left)
        {
            return false;
        }
        FieldInfo fi = typeof(SchedulerInputBehavior).GetField("beginEditTimer", BindingFlags.NonPublic| BindingFlags.Instance);
        Timer beginEditTimer = fi.GetValue(this) as Timer;
        beginEditTimer.Stop();

        if (!this.Scheduler.ReadOnly && sender is AppointmentElement)
        {
            AppointmentElement app = sender as AppointmentElement; 
            this.Scheduler.ShowAppointmentEditDialog(app.Appointment, app.Appointment.MasterEvent != null);
        }

        return false;
    }
}

Workaround: 

private void radScheduler1_CellFormatting(object sender, Telerik.WinControls.UI.SchedulerCellEventArgs e)
{
    if (e.CellElement is SchedulerHeaderCellElement && e.CellElement.Text == "Local")
    {
        e.CellElement.TextAlignment = ContentAlignment.BottomLeft;
    }
}

To reproduce: use the following code snippet:

private BindingList<MyEvent> eventsSource = new BindingList<MyEvent>();
private AppointmentMappingInfo appointmentMappingInfo_g = new AppointmentMappingInfo();

public RadForm2()
{
    InitializeComponent();
}

private void RadForm2_Load(object sender, EventArgs e)
{
    radScheduler1.ActiveViewType = radScheduler2.ActiveViewType = SchedulerViewType.Timeline;
    radScheduler1.GetTimelineView().ShowTimescale(Timescales.Days);
    radScheduler2.GetTimelineView().ShowTimescale(Timescales.Days);
    radScheduler1.GetTimelineView().RangeStartDate = radScheduler2.GetTimelineView().RangeStartDate = new DateTime(2015, 9, 1);
    radScheduler1.GetTimelineView().RangeEndDate = radScheduler2.GetTimelineView().RangeEndDate = new DateTime(2015, 9, 30);
    radScheduler1.GetTimelineView().StartDate = radScheduler2.GetTimelineView().StartDate = new DateTime(2015, 9, 1);
    radScheduler1.GetTimelineView().GetScaling().DisplayedCellsCount = radScheduler2.GetTimelineView().GetScaling().DisplayedCellsCount = 7;

    appointmentMappingInfo_g.Start = "Start";
    appointmentMappingInfo_g.End = "End";
    appointmentMappingInfo_g.Summary = "Subject";
    appointmentMappingInfo_g.Description = "Description";
    appointmentMappingInfo_g.Location = "Location";
    appointmentMappingInfo_g.UniqueId = "Id";

    SchedulerBindingDataSource dataSource_l = new SchedulerBindingDataSource();
    dataSource_l.EventProvider.Mapping = appointmentMappingInfo_g;
    dataSource_l.EventProvider.DataSource = eventsSource;
    radScheduler2.DataSource = dataSource_l;

    FillAppointments();
}

private void FillAppointments()
{
    Appointment appointment = new Appointment(new DateTime(2015, 9, 2), new DateTime(2015, 9, 6), "DU 2 AU 6");
    appointment.AllDay = true;

    radScheduler1.Appointments.BeginUpdate();
    radScheduler1.Appointments.Add(appointment);
    radScheduler1.Appointments.EndUpdate();

    MyEvent appointment2 = new MyEvent(new DateTime(2015, 9, 2), new DateTime(2015, 9, 6), "DU 2 AU 6","","","");
    radScheduler2.Appointments.BeginUpdate();
    eventsSource.Add(appointment2);
    radScheduler2.Appointments.EndUpdate();
}

public class MyEvent
{
    public DateTime Start { get; set; }

    public DateTime End { get; set; }

    public string Subject { get; set; }

    public string Description { get; set; }

    public string Location { get; set; }

    public string UniqueId { get; set; }

    public MyEvent(DateTime start, DateTime end, string subject,
        string description, string location, string uniqueId)
    {
        this.Start = start;
        this.End = end;
        this.Subject = subject;
        this.Description = description;
        this.Location = location;
        this.UniqueId = uniqueId;
    }
}

Workaround: specify the end day with 1 second more:
 MyEvent appointment2 = new MyEvent(new DateTime(2015, 9, 2), new DateTime(2015, 9, 6, 0, 0, 1), "DU 2 AU 6", "", "", "");

To reproduce: please refer to the attached gif file

Dim a1 As New Appointment(DateTime.Today.AddDays(-1), TimeSpan.FromDays(3), "Termin1")
a1.AllDay = True
Dim a2 As New Appointment(DateTime.Today.AddDays(-1), TimeSpan.FromDays(1), "Termin2")
a2.AllDay = True
Me.RadScheduler1.Appointments.Add(a1)
Me.RadScheduler1.Appointments.Add(a2)

Workaround: specify precisely the end date including the time part as well

Dim a1 As New Appointment(DateTime.Today.AddDays(-1), TimeSpan.FromDays(3).Add(TimeSpan.FromMinutes(1)), "Termin1")
a1.AllDay = False
Dim a2 As New Appointment(DateTime.Today.AddDays(-1), TimeSpan.FromDays(2).Add(TimeSpan.FromMinutes(1)), "Termin2")
a2.AllDay = False
 
Me.RadScheduler1.Appointments.Add(a1)
Me.RadScheduler1.Appointments.Add(a2)

Workaround: use your own icon: 

public Form1()
{
    InitializeComponent();
    this.radScheduler1.RecurrenceEditDialogShowing+=radScheduler1_RecurrenceEditDialogShowing;
}

private void radScheduler1_RecurrenceEditDialogShowing(object sender, Telerik.WinControls.UI.RecurrenceEditDialogShowingEventArgs e)
{
    ((RadForm)e.RecurrenceEditDialog).Icon = Properties.Resources.WinFormsIcon;
}

public Form1()
{
    InitializeComponent();
    DateTime d = DateTime.Now.Date; 
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 1, 30, 0), new DateTime(d.Year, d.Month, d.Day, 1, 30, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 8, 30, 0), new DateTime(d.Year, d.Month, d.Day, 9, 0, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 11, 00, 0), new DateTime(d.Year, d.Month, d.Day, 11, 30, 0), "Appointment_Free_0", "", ""));

    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 11, 0, 0), new DateTime(d.Year, d.Month, d.Day, 11, 0, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 10, 30, 0), new DateTime(d.Year, d.Month, d.Day, 11, 0, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 11, 00, 0), new DateTime(d.Year, d.Month, d.Day, 11, 30, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 11, 30, 0), new DateTime(d.Year, d.Month, d.Day, 12, 0, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 14, 0, 0), new DateTime(d.Year, d.Month, d.Day, 14, 30, 0), "Appointment_Free_0", "", ""));
    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 15, 00, 0), new DateTime(d.Year, d.Month, d.Day, 15, 30, 0), "Appointment_Free_0", "", ""));

    radScheduler1.Appointments.Add(new Appointment(new DateTime(d.Year, d.Month, d.Day, 17, 30, 0), new DateTime(d.Year, d.Month, d.Day, 17, 30, 0), "Appointment_Free_0", "", ""));

    radScheduler1.ActiveViewType = SchedulerViewType.Day;

    radScheduler1.EnableExactTimeRendering = true;
}


Workaround: use a custom DayViewAppointmentsTable

 this.radScheduler1.ElementProvider = new MyElementProvider(this.radScheduler1);

public class MyElementProvider : SchedulerElementProvider
{
    public MyElementProvider(RadScheduler scheduler) : base(scheduler)
    {
    }

    protected override T CreateElement<T>(SchedulerView view, object context)
    {
        if (typeof(T) == typeof(DayViewAppointmentsTable))
        {
            return new CustomDayViewAppointmentsTable(view.Scheduler, view, (DayViewAppointmentsArea)context)as T;
        }

        return base.CreateElement<T>(view, context);
    }
}

public class CustomDayViewAppointmentsTable : DayViewAppointmentsTable
{
    public CustomDayViewAppointmentsTable(RadScheduler scheduler, SchedulerView view, DayViewAppointmentsArea area) : base(scheduler, view, area)
    {
    }
    
    protected override IEnumerable<AppointmentElement> CreateAppointmentElements()
    {
        if (this.View != null)
        {
            IList<IEvent> appointmentsInView = new List<IEvent>(this.View.Appointments);
            List<AppointmentElement> elements = DivideAppointmentToElements(appointmentsInView);
            elements.Sort(0, elements.Count, new DateTimeComparer(this.Scheduler));

            foreach (AppointmentElement currentAppointment in elements)
            {
                currentAppointment.RelatedAppointments.Clear();
                currentAppointment.DesiredBounds = new RectangleF();
            }

            foreach (AppointmentElement appointment in elements)
            {
                List<AppointmentElement> intersectingAppointments = this.GetAllAppointmentsInDay(appointment.Start.Day, elements);
                intersectingAppointments.Remove(appointment);
                appointment.RelatedAppointments = intersectingAppointments;
            }

            return elements;
        }
        else
        {
            return new List<AppointmentElement>();
        }
    }

    private List<AppointmentElement> GetAllAppointmentsInDay(int day, List<AppointmentElement> elements)
    {
        List<AppointmentElement> result = new List<AppointmentElement>();
        foreach (AppointmentElement appointment in elements)
        {
            if (appointment.Start.Day == day)
            {
                result.Add(appointment);
            }
        }

        return result;
    }

    private List<AppointmentElement> DivideAppointmentToElements(IList<IEvent> appointmentsInView)
    {
        List<AppointmentElement> childAppointments = new List<AppointmentElement>();
        TimeSpan startTime = TimeSpan.FromMinutes(this.GetDayViewBase().RulerStartScale * 60 + this.GetDayViewBase().RulerStartScaleMinutes);
        TimeSpan endTime = TimeSpan.FromMinutes(this.GetDayViewBase().RulerEndScale * 60 + this.GetDayViewBase().RulerEndScaleMinutes);

        foreach (IEvent app in appointmentsInView)
        {
            SchedulerDayViewBase dayView = this.GetDayViewBase();
            bool allDay = (dayView != null) ? dayView.IsAllDayEvent(app) : false;

            DateTime appStart = this.View.DefaultTimeZone.OffsetTime(app.Start, this.Scheduler.SystemTimeZone);
            DateTime appEnd = this.View.DefaultTimeZone.OffsetTime(app.End, this.Scheduler.SystemTimeZone);

            if (!allDay)
            {
                // Handle > 1 day appointments
                if (appStart.Day != appEnd.Day && !(appEnd.Day - appStart.Day == 1 && appEnd.TimeOfDay == TimeSpan.Zero))
                {
                    AppointmentElement appointment1 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                    appointment1.Start = appStart;
                    appointment1.End = DateHelper.GetEndOfDay(appStart);

                    if (appointment1.Start.TimeOfDay >= endTime)
                    {
                        appointment1.Start = new DateTime(appStart.Year, appStart.Month, 
                            appStart.Day, 0, 0, 0).Add(endTime).AddMinutes(-(int)this.GetDayViewBase().RangeFactor);
                    }

                    AppointmentElement appointment2 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                    appointment2.Start = appEnd.Date;
                    appointment2.End = appEnd;

                    if (appointment1.Start >= this.View.StartDate)
                    {
                        childAppointments.Add(appointment1);
                    }

                    if (appointment2.Start >= this.View.StartDate)
                    {
                        childAppointments.Add(appointment2);
                    }
                }
                else
                {
                    AppointmentElement appointment1 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                    appointment1.Start = appStart;
                    appointment1.End = appEnd;

                    if (appointment1.Start.TimeOfDay < startTime)
                    {
                        appointment1.Start = new DateTime(appStart.Year, appStart.Month, appStart.Day, 0, 0, 0).Add(startTime);
                    }

                    if (appointment1.Start.TimeOfDay >= endTime)
                    {
                        appointment1.Start = new DateTime(appStart.Year, appStart.Month, appStart.Day, 0,
                            0, 0).Add(endTime).AddMinutes(-(int)this.GetDayViewBase().RangeFactor);
                    }

                    if (appointment1.End.TimeOfDay > endTime)
                    {
                        appointment1.End = new DateTime(appEnd.Year, appEnd.Month, appEnd.Day, 0, 0, 0).Add(endTime);
                    }

                    if (appointment1.End.TimeOfDay <= startTime)
                    {
                        appointment1.End = new DateTime(appEnd.Year, appEnd.Month, appEnd.Day, 0, 0,
                            0).Add(startTime).AddMinutes((int)this.GetDayViewBase().RangeFactor);
                    }

                    childAppointments.Add(appointment1);
                }
            }
            else if (!dayView.ShowAllDayArea)
            {
                DateTimeInterval viewInterval = new DateTimeInterval(this.View.StartDate, DateHelper.GetEndOfDay(this.View.EndDate));

                AppointmentElement appointment1 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                appointment1.Start = appStart;
                appointment1.End = DateHelper.GetEndOfDay(appStart);

                DateTimeInterval interval = new DateTimeInterval(appStart, appointment1.End);
                if (interval.IntersectsWith(viewInterval))
                {
                    if (appointment1.Start.TimeOfDay < startTime)
                    {
                        appointment1.Start = new DateTime(appStart.Year, appStart.Month, appStart.Day, 0, 0, 0).Add(startTime);
                    }

                    if (appointment1.Start.TimeOfDay >= endTime)
                    {
                        appointment1.Start = new DateTime(appStart.Year, appStart.Month, appStart.Day, 0, 0,
                            0).Add(endTime).AddMinutes(-(int)this.GetDayViewBase().RangeFactor);
                    }

                    if (appointment1.End.TimeOfDay > endTime)
                    {
                        appointment1.End = new DateTime(appEnd.Year, appEnd.Month, appEnd.Day, 0, 0, 0).Add(endTime);
                    }

                    if (appointment1.End.TimeOfDay <= startTime)
                    {
                        appointment1.End = new DateTime(appEnd.Year, appEnd.Month, appEnd.Day, 0, 0,
                            0).Add(startTime).AddMinutes((int)this.GetDayViewBase().RangeFactor);
                    }

                    childAppointments.Add(appointment1);
                }

                DateTime startDate = appStart.AddDays(1).Date;
                AppointmentElement appointment2 = null;

                while (startDate <= appEnd.Date.AddDays(-1))
                {
                    appointment2 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                    appointment2.Start = startDate;
                    appointment2.End = DateHelper.GetEndOfDay(startDate);
                    interval = new DateTimeInterval(appointment2.Start, appointment2.End);
                    if (interval.IntersectsWith(viewInterval))
                    {
                        childAppointments.Add(appointment2);
                    }
                    startDate = startDate.AddDays(1);
                }

                DateTime endDate = appEnd.Date;
                DateTime endAppointmentDate = appEnd;
                appointment2 = this.CreateAppointmentElement(this.Scheduler, this.View, app);
                appointment2.Start = endDate;
                appointment2.End = endAppointmentDate;

                interval = new DateTimeInterval(endDate, endAppointmentDate);
                if (interval.IntersectsWith(viewInterval) && interval.Start != appStart)
                {
                    childAppointments.Add(appointment2);
                }
            }
        }

        return childAppointments;
    }

    private AppointmentElement CreateAppointmentElement(RadScheduler scheduler, SchedulerView view, IEvent appointment)
    {
        AppointmentElement appointmentElement = null;
        if (scheduler.AppointmentElementFactory != null)
        {
            appointmentElement = scheduler.AppointmentElementFactory.CreateAppointmentElement(scheduler, view, appointment);
        }
        else
        {
            appointmentElement = scheduler.ElementProvider.GetElement<AppointmentElement>(view, appointment);
        }
        return appointmentElement;
    }
}

Please refer to the attached gif file.

To reproduce:

Public Class Form1
    Sub New()
         
        InitializeComponent()

        Me.RadScheduler1.EnableExactTimeRendering = True
        
        Dim dt = DateTime.Now
        Me.RadScheduler1.Appointments.Add(New Appointment(dt.AddMinutes(-10).AddSeconds(1), Now, "A1"))
        Me.RadScheduler1.Appointments.Add(New Appointment(dt.AddMinutes(-15), DateTime.Now.AddMinutes(-10), "A2"))
        Me.RadScheduler1.GetTimelineView().StartDate = DateAdd(DateInterval.Minute, -15, Now)

        Dim customScale As CustomTimescalePerMinute = New CustomTimescalePerMinute()
        Dim timelineView As SchedulerTimelineView = Me.RadScheduler1.GetTimelineView()
        timelineView.SchedulerTimescales.Add(customScale)

        timelineView.ShowTimescale(customScale)
        Dim currentScaling As SchedulerTimescale = timelineView.GetScaling()
        currentScaling.DisplayedCellsCount = 15
    End Sub
End Class

Public Class CustomTimescalePerMinute
Inherits MinutesTimescale
    Public Overrides ReadOnly Property ScalingFactor() As Integer
        Get
            Return 1
        End Get
    End Property
End Class

Note: the attached gif file illustrates the behavior. Initially, the first appointment's end is not rendered in the correct time slot. After scrolling, it is displayed correctly.

Workaround: force scrolling

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Dim t As SchedulerTimelineViewElement = TryCast(Me.RadScheduler1.SchedulerElement.ViewElement, SchedulerTimelineViewElement)
    Dim value = t.NavigationElement.Value
    t.NavigationElement.Value += 1
    Me.RadScheduler1.SchedulerElement.RefreshViewElement()
    t.NavigationElement.Value = value
End Sub

In RadScheduler I have appointment with End set to new DateTime(9999, 12, 22) (or greater). When I switch to Month view the exception is thrown:

The added or subtracted value results in an un-representable DateTime.

Found in version: 2016.2.608.40
It was working in version:  2013.2.724.40

To reproduce:

 public Form1()
 {
     InitializeComponent();

     this.radScheduler1.ActiveViewType = SchedulerViewType.Month;
     this.radScheduler1.Appointments.Add(new Appointment(new DateTime(9999,12,22),TimeSpan.FromMinutes(30),"A1"));
 }
 

To reproduce:
Sub New() 
    InitializeComponent()

    Dim colors() As Color = {Color.LightBlue, Color.LightGreen, Color.LightYellow, Color.Red, _
        Color.Orange, Color.Pink, Color.Purple, Color.Peru, Color.PowderBlue}
    Dim names() As String = {"Alan Smith", "Anne Dodsworth", "Boyan Mastoni", "Richard Duncan", "Maria Shnaider"}
    For i As Integer = 0 To names.Length - 1
        Dim resource As New Telerik.WinControls.UI.Resource()
        resource.Id = New EventId(i)
        resource.Name = names(i)
        resource.Color = colors(i)
        Me.RadScheduler1.Resources.Add(resource)
    Next i
    Me.RadScheduler1.GroupType = GroupType.Resource
    Me.RadScheduler1.ActiveView.ResourcesPerView = Me.RadScheduler1.Resources.Count

    Me.RadScheduler1.ActiveViewType = SchedulerViewType.Timeline

    Dim rand As New Random
    For index = 1 To 20
        Dim a As New Appointment(DateTime.Now.AddDays(index), TimeSpan.FromHours(2), "A" & index)
        a.ResourceId = Me.RadScheduler1.Resources(rand.Next(0, Me.RadScheduler1.Resources.Count)).Id
        Me.RadScheduler1.Appointments.Add(a) 
    Next
    
    Dim timelineView As SchedulerTimelineView = Me.RadScheduler1.GetTimelineView()
     
    Dim oneMinute As New OneMinuteTimescale()
    timelineView.SchedulerTimescales.Add(oneMinute)

    oneMinute.Visible = True 
End Sub

Public Class OneMinuteTimescale
Inherits MinutesTimescale
    Public Overrides ReadOnly Property Name As String
        Get
            Return "OneMinuteTimescale"
        End Get
    End Property
    Public Overrides ReadOnly Property ScalingFactor() As Integer
        Get
            Return 1
        End Get
    End Property
End Class

Workaround: decrease the range: 

 timelineView.RangeStartDate = DateTime.Today
 timelineView.RangeEndDate = timelineView.RangeStartDate.AddDays(1)

To reproduce:

public Form1()
{
    InitializeComponent();
    this.radScheduler1.ActiveViewType = Telerik.WinControls.UI.SchedulerViewType.Month;

    CultureInfo culture = new CultureInfo("en-US");
    culture.DateTimeFormat.FirstDayOfWeek = DayOfWeek.Monday;
    this.radScheduler1.Culture = culture;
   
    Appointment a = new Appointment(new DateTime(2016, 8, 29, 0, 0, 0), new DateTime(2016, 9, 5, 0, 0, 0), "Meeting");

    this.radScheduler1.Appointments.Add(a);

    this.radScheduler1.FocusedDate = new DateTime(2016, 9, 1);

    this.radScheduler1.EnableExactTimeRendering = true;
}

When you run the application starting scrolling with the mouse wheel up/down.

Workaround: do not set the FirstDayOfWeek to Monday.

To reproduce:

            Appointment a = new Appointment(DateTime.Now, TimeSpan.FromHours(20),"Meeting");
            a.StatusId = this.radScheduler1.Statuses.Last().Id;
            this.radScheduler1.Appointments.Add(a);

            this.radScheduler1.ShowAppointmentStatus = false;

The status for AppointmentElements is shown although it shouldn't.

To reproduce:
RadScheduler radScheduler1 = new RadScheduler();
public Form1()
{
    InitializeComponent();
    radScheduler1.Top += 100;
    radScheduler1.Parent = this;
    this.radSchedulerNavigator1.AssociatedScheduler = radScheduler1;
    this.radScheduler1.ActiveViewType = SchedulerViewType.Timeline;
  

    Color[] colors = new Color[]{Color.LightBlue, Color.LightGreen, Color.LightYellow,
        Color.Red, Color.Orange, Color.Pink, Color.Purple, Color.Peru, Color.PowderBlue};
    string[] names = new string[]{"Alan Smith", "Anne Dodsworth",
         "Boyan Mastoni", "Richard Duncan", "Maria Shnaider"};
    for (int i = 0; i < names.Length; i++)
    {
        Resource resource = new Resource();
        resource.Id = new EventId(i);
        resource.Name = names[i];
        resource.Color = colors[i];
   this.radScheduler1.Resources.Add(resource);
    }

    this.radScheduler1.GroupType = GroupType.Resource;
    this.radScheduler1.ActiveView.ResourcesPerView = 2;
}

private void radButton1_Click(object sender, EventArgs e)
{
    SchedulerWeeklyCalendarPrintStyle weeklyCalendarStyle = new SchedulerWeeklyCalendarPrintStyle();
    weeklyCalendarStyle.AppointmentFont = new System.Drawing.Font("Segoe UI", 12, FontStyle.Regular);
    weeklyCalendarStyle.HeadingAreaHeight = 120;
    weeklyCalendarStyle.HoursColumnWidth = 30;

    this.radScheduler1.PrintStyle = weeklyCalendarStyle;

    this.radScheduler1.PrintPreview();
}

Workaround:
Change the view before printing.

If you want to show the borders for the weekdays, the left most border is not shown because another element is over the cell. It is not possible to hide this top left cell and show the left border for Sunday.

This is reproducible not only with Material theme but with the other themes as well.

Workaround:

        private void radScheduler1_CellFormatting(object sender, Telerik.WinControls.UI.SchedulerCellEventArgs e)
        {
            e.CellElement.ZIndex = 0;
        }

How to reproduce:
public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
    public RadForm1()
    {
        InitializeComponent();

        Resource resource1 = new Resource();
        resource1.Id = new EventId(1);
        resource1.Name = "Resource 1";
        resource1.Color = Color.Blue;

        Resource resource2 = new Resource();
        resource2.Id = new EventId(2);
        resource2.Name = "Resource 2";
        resource2.Color = Color.Green;

        Resource resource3 = new Resource();
        resource3.Id = new EventId(3);
        resource3.Name = "Resource 3";
        resource3.Color = Color.Red;

        this.radScheduler1.Resources.Add(resource1);
        this.radScheduler1.Resources.Add(resource2);
        this.radScheduler1.Resources.Add(resource3);
    }

    private void RadForm1_Load(object sender, EventArgs e)
    {
        this.radScheduler1.GroupType = GroupType.Resource;
        ((SchedulerViewGroupedByResourceElementBase)this.radScheduler1.ViewElement).ResourceStartIndex = 2;
    }

    private void radButton1_Click(object sender, EventArgs e)
    {
        this.radScheduler1.Resources.RemoveAt(0);
    }
}


Workaround: 
public partial class RadForm1 : Telerik.WinControls.UI.RadForm
{
    public RadForm1()
    {
        InitializeComponent();

        Resource resource1 = new Resource();
        resource1.Id = new EventId(1);
        resource1.Name = "Resource 1";
        resource1.Color = Color.Blue;

        Resource resource2 = new Resource();
        resource2.Id = new EventId(2);
        resource2.Name = "Resource 2";
        resource2.Color = Color.Green;

        Resource resource3 = new Resource();
        resource3.Id = new EventId(3);
        resource3.Name = "Resource 3";
        resource3.Color = Color.Red;

        this.radScheduler1.Resources.Add(resource1);
        this.radScheduler1.Resources.Add(resource2);
        this.radScheduler1.Resources.Add(resource3);
    }

    private void RadForm1_Load(object sender, EventArgs e)
    {
        this.radScheduler1.GroupType = GroupType.Resource;
        ((SchedulerViewGroupedByResourceElementBase)this.radScheduler1.ViewElement).ResourceStartIndex = 2;
    }

    private void radButton1_Click(object sender, EventArgs e)
    {
        this.radScheduler1.GroupType = GroupType.None;
        this.radScheduler1.Resources.RemoveAt(0);
        this.radScheduler1.GroupType = GroupType.Resource;
    }
}