In the following scenario, we have enabled the pager functionality of the control. If we move to a different page and then set the DataSource to Null, the page index will not be reset. 

The EnableHotTracking property works only in the first level hierarchy. The lower levels still get highlighted.

Steps to recreate:

• click on the button on the top row
• press the down key on the keyboard
• Press Space key to select new button, the button on the top row is clicked

System.ArgumentException: 'An item with the same key has already been added.' when the data source contains DateTime with the same hour, minute, and seconds part (only milliseconds are different):

The following line gets serialized when set this property:

((Telerik.WinControls.UI.GridSelectCheckBoxElement)(this.radGridView1.GetChildAt(0).GetChildAt(0).GetChildAt(2).GetChildAt(0).GetChildAt(0).GetChildAt(1).GetChildAt(0).GetChildAt(1).GetChildAt(0))).Visibility = Telerik.WinControls.ElementVisibility.Collapsed;

Call stack:

Telerik.WinControls.GridView.dll!Telerik.WinControls.UI.GridGroupHeaderRowElement.Initialize(Telerik.WinControls.UI.GridViewRowInfo rowInfo) Line 100
	at Telerik.WinControls.UI\GridGroupHeaderRowElement.cs(100)
Telerik.WinControls.GridView.dll!Telerik.WinControls.Export.GridExportUtils.GetRowHeight(Telerik.WinControls.UI.RadGridView radGridView, Telerik.WinControls.UI.RowElementProvider rowProvider, Telerik.WinControls.UI.CellElementProvider cellProvider, Telerik.WinControls.UI.GridViewRowInfo gridViewRowInfo, bool exportVisualSettings) Line 158
	at Telerik.WinControls.Export\GridExportUtils.cs(158)
Telerik.WinControls.GridView.dll!Telerik.WinControls.Export.GridViewSpreadExport.AddRow(Telerik.WinControls.UI.GridViewRowInfo gridViewRowInfo, int rowIndex) Line 960