I'm trying to include more than just the summary in the tooltip. I put the code below in the AppointmentFormatting event but I get a stack overflow unless I only include the first line that sets the tooltip to the summary, basically leaving it unchanged.

An AppointmentChanged event should be added to RadScheduler that can be handled in VB.NET by the 'Handles' approach.

Resolution: 
The AppointmentChanged event is added which is the Appointments.CollectionChanged event with ItemChanged action.

Open TimeZones example in the Demo application, navigate to TimelineView, set scale to be day, month or year, switch to MonthView then switch back to TimelineView. A NullReferenceException will be thrown.

If one drags an appointment from the all day area to the first cell of the same day which starts at 12:00 AM or 0:00 and vice versa the AppointmentMoving event does not fire.

RadReminderBindableObject remains in memory when using the ContainsRemindObject or RemoveRemindObject methods.

When I you set an appointment to something like:
Start Time - 1/15/2013 4:00:00 PM
End Time - 1/16/2013 12:00:00 AM

the appointment element in MonthView will span on both 1/15 and 1/16 cells.

If you run RadScheduler on a system with 120 DPI, you will see that header cells are misplaced and also the text on the ruler is larger than the rows.

DECLINED: This is a limitation of the DataSet model. The last section "Updating the database" of this help article http://www.telerik.com/help/winforms/scheduler-data-binding-data-binding-walkthrough.html explains how you can overcome this.

Steps to reproduce:
1. Bind RadScheduler to a database with appointments and resources.
2. Add a few appointments, save and close the form.
3. Delete the last added appointment, save and close the form.
4. When you add a new appointment and try to save, an SQL exception will be thrown.

Use the RadSchedulerDB_Objects project from the "Introduction to RadScheduler for WinForms" webinar (http://tv.telerik.com/watch/winforms/radscheduler/introduction-radscheduler-winforms). If you run this project without opening the designer, the binding works correctly. If you open the form in the designer and then run the project, only one empty appointment will be displayed. The issue occurs because when opening the form, the following lines are removed from the designer:
((System.ComponentModel.ISupportInitialize)(this.schedulerBindingDataSource1.EventProvider)).BeginInit();
((System.ComponentModel.ISupportInitialize)(this.schedulerBindingDataSource1.ResourceProvider)).BeginInit();

1. Create a new project and add RadScheduler in week view mode.
2. Add all day event.
3. Export the all day event in iCal format.
4. Clear all appointments and import the exported file.

When you drag an appointment to a cell in MonthView, its start time will be reset to 12:00AM.

To workaround the issue, use the following code:

    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            this.radScheduler1.SchedulerElement.DragDropBehavior = new MyDraggingBehavior(this.radScheduler1.SchedulerElement);
        }
    }

    class MyDraggingBehavior : AppointmentDraggingBehavior
    {
        public MyDraggingBehavior(RadSchedulerElement element)
            : base(element) { }

        public override bool Move(DateTime newDate)
        {
            if (this.Scheduler.ActiveViewType == SchedulerViewType.Month)
            {
                newDate = newDate.Add(this.ActiveFeedback.AssociatedAppointment.Start.TimeOfDay);
            }
            return base.Move(newDate);
        }
    }

Steps to reproduce:
1. Subscribe for the scheduler Appointments.CollectionChanged event.
2. Add a recurring appointment and delete a single occurrence.
You will see that the event is fired and the action is Add.

Currently the default RadSchedulerReminder behavior is to remind about appointments before Start date occurs, e.g 15 min before start date. Improve the RadSchedulerReminder to support reminder before the appointment ends too.

If one sets the AllowAppointmentMove to false he can still drag drop the all day appointments in the headers of a day view.

Currently RadScheduler does not support undo/redo operations and history.

CLOSED: This should be part of the business logic of your application and not built-in in RadScheduler

Setting the AllowAppointmentMove property to false does not prevent appointments from being dragged.

If you add multiple intervals to MultiDayView and enable grouping, you will see that the displayed dates are not correct.

The date label in RadSchedulerNavigator is not updated when you change the Intervals collection in multiday view.

Add a grouped by resource RadScheduler in timeline view, set the scaling to be Month and then right click an appointment. An exception will be thrown.

If you have 3 appointments at 13:00, 2 of which end at 14:00 and the third ends at 17:00
and then you add another appointment that starts at 14:30 and stops at 15:30, the width of this appointment is 1/3 of the total with for the day although there is room for this appointment to be 2/3 of the width of that day.