WORKAROUND:
1. Create a custom GridTableElement and override the ProcessColumnEvent method.
2. Create a custom TableViewDefinition and override the CreateViewUIElement to return the custom table element.
3. Assign the custom view definition to the grid's ViewDefinition property

public class CustomGridTableElement : GridTableElement
{
    protected override GridViewEventResult ProcessColumnEvent(GridViewColumn column, GridViewEvent eventData)
    {
        if (eventData.Info.Id == KnownEvents.PropertyChanged)
        {
            RadPropertyChangedEventArgs args = eventData.Arguments[0] as RadPropertyChangedEventArgs;

            if (args.Property == GridViewColumn.IsVisibleProperty)
            {
                ViewElement.UpdateRowsWhenColumnsChanged();

                if (this.GridViewElement.AutoSizeRows)
                {
                    foreach (GridViewRowInfo row in this.ViewTemplate.Rows)
                    {
                        row.Height = -1;
                    }

                    this.UpdateLayout();
                    this.RowScroller.UpdateScrollRange();
                }

                return null;
            }
        }

        return base.ProcessColumnEvent(column, eventData);
    }

    protected override Type ThemeEffectiveType
    {
        get { return typeof(GridTableElement); }
    }
}


public class CustomTableViewDefinition : TableViewDefinition
{
    public override IRowView CreateViewUIElement(GridViewInfo viewInfo)
    {
        return new CustomGridTableElement();
    }
}


this.radGridView1.ViewDefinition = new CustomTableViewDefinition();

One should be able to set the maximum row height when the rows are auto sized and the visual styles are exported.
 

To reproduce:
Open the attached project, select two rows and delete them.

Workaround:
private void RadGridView1_RowValidating(object sender, Telerik.WinControls.UI.RowValidatingEventArgs e)
{
    if (e.RowIndex != -1)
    {
       
    }
}

To reproduce:

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.ProductsTableAdapter.Fill(Me.NwindDataSet.Products)
    Me.CategoriesTableAdapter.Fill(Me.NwindDataSet.Categories)

    RadGridView1.AutoGenerateHierarchy = True
    RadGridView1.DataSource = Me.NwindDataSet
    RadGridView1.DataMember = "Categories"

    Me.RadGridView1.MasterTemplate.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill
    Me.RadGridView1.MasterTemplate.Templates(0).AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill

    Me.RadGridView1.UseScrollbarsInHierarchy = True
End Sub

Private Sub RadGridView1_ViewCellFormatting(sender As Object, e As CellFormattingEventArgs) Handles RadGridView1.ViewCellFormatting
    If e.Row.HierarchyLevel > 0 Then
        e.CellElement.TableElement.RowHeaderColumnWidth = 100
    End If
End Sub

To reproduce: make sure only the first row is selected then Shift select row 3.
DataTable dt = new DataTable();

dt.Columns.Add("Value", typeof(int));
dt.Columns.Add("Date", typeof(DateTime));
dt.Columns.Add("Description", typeof(string));

for (int index = 0; index < 15; index++)
{
    dt.Rows.Add(new object[] { index % 5, DateTime.Now.AddSeconds(10), "Index = " + index });
}

radGridView1.DataSource = dt;
radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
radGridView1.MultiSelect = true;

foreach (GridViewColumn col in this.radGridView1.Columns)
{
    ConditionalFormattingObject obj = new ConditionalFormattingObject("Value",
        ConditionTypes.Equal,
        col.Index.ToString(),
        "",
        true);
    obj.RowBackColor = Color.SkyBlue;
    obj.RowForeColor = Color.Red;
    obj.TextAlignment = ContentAlignment.MiddleRight;
    obj.ApplyOnSelectedRows = false;
    this.radGridView1.Columns[0].ConditionalFormattingObjectList.Add(obj);
}

Workaround: use the CellFormatting event to apply the desired formatting by using the API for overriding theme settings: 

http://docs.telerik.com/devtools/winforms/gridview/cells/formatting-cells
http://docs.telerik.com/devtools/winforms/telerik-presentation-framework/override-theme-settings-at-run-time

How to reproduce: 

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();

        this.radGridView1.DataSource = this.GetData();
        this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;
        this.radGridView1.Columns[0].DisableHTMLRendering = false;

        this.radGridView1.PrintCellFormatting += radGridView1_PrintCellFormatting;
    }

    private void radGridView1_PrintCellFormatting(object sender, Telerik.WinControls.UI.PrintCellFormattingEventArgs e)
    {
        e.PrintCell.EnableHtmlTextRendering = true;
    }

    private DataTable GetData()
        {
            DataTable dt = new DataTable();

            dt.Columns.Add("Name", typeof(string));
            dt.Columns.Add("Date", typeof(DateTime));
            dt.Columns.Add("Bool", typeof(bool));
            dt.Columns.Add("Description", typeof(string));
            for (int i = 0; i < 10; i++)
            {
                for (int j = 0; j < 5; j++)
                {
                    dt.Rows.Add(@"<html><b>Name " + j, DateTime.Now.AddDays(i), i % 2 == 0 ? true : false, "Description " + i);
                }
            }

            return dt;
        }

    private void radButton1_Click(object sender, EventArgs e)
    {
        GridPrintStyle style = new GridPrintStyle();
        style.FitWidthMode = PrintFitWidthMode.FitPageWidth;
        style.PrintGrouping = true;
        style.PrintSummaries = false;

        style.PrintHeaderOnEachPage = true;
        style.PrintHiddenColumns = false;
        style.CellPadding = new Padding(100, 0, 0, 0);

        this.radGridView1.PrintStyle = style;
        this.radGridView1.PrintPreview();
    }
}


Workaround: refer to the attached project

To reproduce:

private void Form1_Load(object sender, EventArgs e)
{
    this.productsTableAdapter.Fill(this.nwindDataSet.Products);
    this.radGridView1.BestFitColumns(BestFitColumnMode.AllCells);
}

private void radGridView1_ViewCellFormatting(object sender, Telerik.WinControls.UI.CellFormattingEventArgs e)
{
    if (e.CellElement is GridGroupContentCellElement)
    {
        e.CellElement.TextWrap = true;
    }
    else
    {
        e.CellElement.ResetValue(LightVisualElement.TextWrapProperty, ValueResetFlags.Local);
    }
}

Workaround: set the AutoSizeColumnsMode property to GridViewAutoSizeColumnsMode.Fill and use the ViewCellFormatting event to wrap the text: 

private void radGridView1_ViewCellFormatting(object sender, Telerik.WinControls.UI.CellFormattingEventArgs e)
{
    if (e.CellElement is GridGroupContentCellElement)
    {
        e.CellElement.TextWrap = true;
    }
    else
    {
        e.CellElement.ResetValue(LightVisualElement.TextWrapProperty, ValueResetFlags.Local);
    }
}

Please find attached a sample project.

1. Select the new row and activate te editor.
2. Do not enter any value and click outside the new row. The exception is thrown.

Workaround: bind directly to the query result:
this.radGridView1.DataSource = (from p in context.Customers select p).ToList();

Workaround: instead of using the default alternating row color for the mentioned themes, use the override theme setting in the CellFormatting event: http://www.telerik.com/help/winforms/tpf-override-theme-settings-at-run-time.html
private void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)
{
    if (e.Row is GridViewDataRowInfo)
    {
        if (e.RowIndex % 2 == 0)
        {
            e.CellElement.SetThemeValueOverride(LightVisualElement.BackColorProperty, Color.Red, "");
            e.CellElement.SetThemeValueOverride(LightVisualElement.DrawFillProperty, true, "");
            e.CellElement.SetThemeValueOverride(LightVisualElement.GradientStyleProperty, GradientStyles.Solid, "");
        }
        else
        {
            e.CellElement.ResetThemeValueOverride(LightVisualElement.BackColorProperty, "");
            e.CellElement.ResetThemeValueOverride(LightVisualElement.DrawFillProperty, "");
            e.CellElement.ResetThemeValueOverride(LightVisualElement.GradientStyleProperty, ""); 
        }
    }
}

Currently the Paging functionality does not support server side operations. It should be extended to support them, e.g. with EntityFramework and Telerik Data Access

To reproduce:
Search a specific text by focusing the search box programmatically and the using the SendKeys method:
private void radButton1_Click(object sender, EventArgs e)
{
    GridSearchCellElement searchCell = radGridView1.TableElement.GetCellElement(radGridView1.MasterView.TableSearchRow, null) as GridSearchCellElement;
    if (searchCell != null)
    {
        searchCell.SearchTextBox.Focus();
        searchCell.SearchTextBox.Text = string.Empty;
        SendKeys.Send("t");
        SendKeys.Send("e");
        SendKeys.Send("s");
        SendKeys.Send("t");
    }
}

Workaround: 
Repeat the search in the SearchProgressChanged event:

radGridView1.MasterView.TableSearchRow.SearchProgressChanged += TextationSearchProgressHandler;

protected void TextationSearchProgressHandler(object sender, SearchProgressChangedEventArgs e)
{
    if (e.SearchFinished && null != radGridView1.TableElement)
    {
        GridSearchCellElement searchCell = radGridView1.TableElement.GetCellElement(radGridView1.MasterView.TableSearchRow, null) as GridSearchCellElement;
        if (searchCell != null
             && searchCell.SearchTextBox.TextBoxItem.Text != e.SearchCriteria)
        {
            radGridView1.MasterView.TableSearchRow.Search(searchCell.SearchTextBox.TextBoxItem.Text);
        }
    }
}

To reproduce:

public Form1() 
{
    InitializeComponent();

    DataTable dt = new DataTable();
    for (int i = 0; i < 5; i++)
    {
        dt.Columns.Add("Col"+i);
    }
    for (int i = 0; i < 2000; i++)
    {
        DataRow row = dt.NewRow();
        foreach (DataColumn col in dt.Columns)
        {
            row[col.ColumnName] = "Data" + i + "." + dt.Columns.IndexOf(col);
        }
        dt.Rows.Add(row);
    }
    this.radGridView1.DataSource = dt;
    this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;
}

private void radButton1_Click(object sender, EventArgs e)
{
    RadPrintPreviewDialog dialog = new RadPrintPreviewDialog();
    dialog.Document = this.radPrintDocument1;
    dialog.ShowDialog();
}

Workaround: this.radGridView1.AutoSizeRows = true;

To reproduce: use the following code snippet. You will notice that the "Accounting Manager" group is missing.

private void Form1_Load(object sender, EventArgs e)
{ 
    this.customersTableAdapter.Fill(this.nwindDataSet.Customers);

    this.radGridView1.DataSource = this.customersBindingSource;

    ColumnGroupsViewDefinition view = new ColumnGroupsViewDefinition();
    view.ColumnGroups.Add(new GridViewColumnGroup("Customer Contact"));
    view.ColumnGroups.Add(new GridViewColumnGroup("Details"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Address"));
    view.ColumnGroups[1].Groups.Add(new GridViewColumnGroup("Contact"));
    view.ColumnGroups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[0].Rows[0].ColumnNames.Add("CompanyName");
    view.ColumnGroups[0].Rows[0].ColumnNames.Add("ContactName");
    view.ColumnGroups[0].Rows[0].ColumnNames.Add("ContactTitle");
    view.ColumnGroups[1].Groups[0].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[0].Rows[0].ColumnNames.Add("Address");
    view.ColumnGroups[1].Groups[0].Rows[0].ColumnNames.Add("City");
    view.ColumnGroups[1].Groups[0].Rows[0].ColumnNames.Add("Country");
    view.ColumnGroups[1].Groups[1].Rows.Add(new GridViewColumnGroupRow());
    view.ColumnGroups[1].Groups[1].Rows[0].ColumnNames.Add("Phone");
    view.ColumnGroups[1].Groups[1].Rows[0].ColumnNames.Add("Fax");
    radGridView1.ViewDefinition = view;

    GroupDescriptor descriptor = new GroupDescriptor();
    descriptor.GroupNames.Add("ContactTitle", ListSortDirection.Ascending);
    this.radGridView1.GroupDescriptors.Add(descriptor);

    this.radGridView1.Groups[0].GroupRow.IsPinned = true;
}

Please refer to the attached screenshot and sample video.

Workaround:
public class CustomGrid : RadGridView
{
    public override string ThemeClassName  
    { 
        get 
        { 
            return typeof(RadGridView).FullName;  
        }
    }

    protected override void OnKeyPress(KeyPressEventArgs e)
    {
        this.BeginEdit();
        if (this.GridViewElement.ActiveEditor is RadDropDownListEditor)
        {
            string symbol = e.KeyChar.ToString();
            RadDropDownListEditor editor = this.GridViewElement.ActiveEditor as RadDropDownListEditor;
            RadDropDownListEditorElement element = editor.EditorElement as RadDropDownListEditorElement;

            if ((element.AutoCompleteMode & AutoCompleteMode.Suggest) == AutoCompleteMode.Suggest)
            {
                element.EditableElementText += symbol;
                element.EditableElement.SelectionStart = 1;
                element.EditableElement.SelectionLength = 0;
            }
        }
        base.OnKeyPress(e);
    }
}

To reproduce:

private void Form1_Load(object sender, EventArgs e)
{
    this.productsTableAdapter.Fill(this.nwindDataSet.Products);
    this.categoriesTableAdapter.Fill(this.nwindDataSet.Categories);
    
    radGridView1.AllowSearchRow = true;
    radGridView1.DataSource = nwindDataSet.Categories;
    radGridView1.MasterTemplate.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
    radGridView1.UseScrollbarsInHierarchy = true;

    GridViewTemplate template = new GridViewTemplate();
    template.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
    template.DataSource = nwindDataSet.Products;
    radGridView1.MasterTemplate.Templates.Add(template);

    GridViewRelation relation = new GridViewRelation(radGridView1.MasterTemplate);
    relation.ChildTemplate = template;
    relation.RelationName = "CategoriesProducts";
    relation.ParentColumnNames.Add("CategoryID");
    relation.ChildColumnNames.Add("CategoryID");
    radGridView1.Relations.Add(relation); 
}

Workaround:
private void radGridView1_CurrentRowChanged(object sender, CurrentRowChangedEventArgs e)
{
    if (this.radGridView1.CurrentRow != null)
    {
        if (this.radGridView1.CurrentRow.HierarchyLevel > 0)
        {
            tableElement.ScrollToRow((GridViewHierarchyRowInfo)(this.radGridView1.CurrentRow).Parent);
             this.radGridView1.TableElement.EnsureRowVisible((GridViewHierarchyRowInfo)(this.radGridView1.CurrentRow).Parent);
            tableElement.ScrollToRow(this.radGridView1.CurrentRow);
            tableElement.EnsureRowVisible(this.radGridView1.CurrentRow);
        }
    }
}

To reproduce: use the following code snippet. From the filtering box, when you select "Null" and then select "All", the following error occurs:
Item has already been added. Key in dictionary: '(Blanks)'  Key being added: '(Blanks)'

DataTable dt = new DataTable();
dt.Columns.Add("Id", typeof(int));
dt.Columns.Add("Name", typeof(string));

dt.Rows.Add(1,"A");
dt.Rows.Add(2, "");
dt.Rows.Add(3, null);
dt.Rows.Add(4, "B");
dt.Rows.Add(5, "C");
dt.Rows.Add(6, "");
this.radGridView1.DataSource = dt;
this.radGridView1.AutoSizeColumnsMode = Telerik.WinControls.UI.GridViewAutoSizeColumnsMode.Fill;
this.radGridView1.EnableFiltering = true;
this.radGridView1.ShowFilteringRow = false;
this.radGridView1.ShowHeaderCellButtons = true;

Workaround:  this.radGridView1.FilterPopupInitialized += radGridView1_FilterPopupInitialized;

RadListFilterDistinctValuesTable selectedValues;

private void radGridView1_FilterPopupInitialized(object sender, Telerik.WinControls.UI.FilterPopupInitializedEventArgs e)
{
    RadListFilterPopup popup = e.FilterPopup as RadListFilterPopup;
    selectedValues = popup.MenuTreeElement.SelectedValues;
    popup.MenuTreeElement.TreeView.NodeCheckedChanged += TreeView_NodeCheckedChanged;
}

private void TreeView_NodeCheckedChanged(object sender, TreeNodeCheckedEventArgs e)
{
    if (e.Node.CheckState == Telerik.WinControls.Enumerations.ToggleState.Off)
    {
        if (selectedValues.Contains(e.Node.Text))
        {
            selectedValues.Remove(e.Node.Text);
        }
    }
}

Workaround: use a custom BaseGridBehavior

public Form1()
{
    InitializeComponent();

    this.radGridView1.GridBehavior = new MyBaseGridBehavior();
}

public class MyBaseGridBehavior : BaseGridBehavior
{
    public override bool ProcessKey(KeyEventArgs keys)
    {
        if (keys.Control && this.GridControl.CurrentColumn == null)
        {
            return false;
        }

        return base.ProcessKey(keys);
    }
}

Add a Card view layout.

To reproduce:
radGridView1.GridNavigator.SelectFirstRow();
for (int i = 0; i < radGridView1.RowCount; i++)
{
    var result = radGridView1.GridNavigator.SelectNextRow(1);
}

Workaround:
- Move to the last row first:
radGridView1.GridNavigator.SelectLastRow();

Workaround: suspend columns notifications when preview dropping and resume the notification after the drag drop service has stopped:

Dim svc As RadDragDropService = Me.RadGridView1.GridViewElement.GetService(Of RadDragDropService)()
AddHandler svc.Stopped, svc_Stopped
AddHandler svc.PreviewDragDrop, AddressOf svc_PreviewDragDrop

Private Sub svc_PreviewDragDrop(sender As Object, e As RadDropEventArgs)
    For Each col As GridViewColumn In Me.RadGridView1.Columns
        col.SuspendPropertyNotifications()
    Next
End Sub

Private Function svc_Stopped() As Object
    For Each col As GridViewColumn In Me.RadGridView1.Columns
        col.ResumePropertyNotifications()
    Next
End Function