GridViewHeaderCell are not draggable when RadGridView is hosted in DropDownButton.DropDownContent. Trying to drag a cell does not trigger drag events.

The problem should be resolved with lib version 2015.3.1012.

The designer crashes with this exception:
InvalidOperationException: 'GridViewColumnGroupRow' TargetType does not match type of element 'GridViewColumnGroupRow'.

See the attached screenshot. It's from a new project, after clean and rebuild.

Visual studio: 2015
Telerik UI for wpf: 2015.2
Implicit styles, Windows8 theme.

* The problem is not theme specific. As a workaround, use no xaml binaries instead of xaml files.

When the HorizontalContentAlignment of the GridViewCheckBoxColumn's CellStyle setting to Center, the checkboxes in the columns remain on the left side. If another theme like OfficeBlack is used, the checkboxes go on the center.

RadGridView.ValidationType property will be available with R2 2016. 

A kind of a workaround for the user: resize any column/the entire window or collapse the row details.

Workaround is to specify that the format string should contain only the required member path:

<telerik:GridViewDynamicHyperlinkColumn Header="ID" DataMemberBinding="{Binding ID}" NavigateUrlMemberPaths="WebUrl" NavigateUrlFormatString="{} {0}"  TargetName="_blank"/>

As a workaround, one can look this up by accessing the Object/DbContext directly.

Will be available with LIB version 2015.3.1026.

The issue seems to be a bug with UI Row Virtualization since once I set it to False, it did not occur any more. You can also refer to the documentation on UI Virtualization: http://docs.telerik.com/devtools/wpf/controls/radgridview/features/ui-virtualization.html