In addition the AutoExpandGroups="False" is not respected and it only occurs when the GroupRenderMode is set to "Nested". As a workaround you can set the GroupRenderMode to "Flat".

- Add text box and RadGridView to silverlight app
- Add one editable row and multiple read only rows after that to a RadGridView. 
- Go to last cell of first row and double click for edit mode.
- Press tab

Focus should go to text box, instead silverlight hangs.

Find attached sample application where this can be reproduced.

reproducible in themes where foreground of cells is changed on selected (i.e. VisualStudio2013)

Workaround:
add cell template to the column

<telerik:GridViewDataColumn.CellTemplate>
    <DataTemplate>
        <TextBlock Text="{Binding Property, Converter={StaticResource converter}}" />
    </DataTemplate>
</telerik:GridViewDataColumn.CellTemplate>

This is reproducible in the Paging Before Grouping demo. If you remove the grouping by the Country column by clicking on the X button of the group, the indent of the group expander will not be collapsed. See the attached video. Note that this reproduces only once when the example loads.

The vertical scrollbar of the RadGridView control disappears when hosted in a RadExpander control with its ExpandDirection set to Right. Initially the scrollbar is shown but if you collapse and then expand the expander control, the scrollbar is missing.

To work this around, stop the RadExpander's animation.
<telerik:RadExpander telerik:AnimationManager.IsAnimationEnabled="False" />

The Gridview Distinct Filters can't be reuse if the filtering panel is close.

When the filter panel is reopen selecting or deselecting distinct filter have no effect.

This is reproductible in telerik demo in any gridview with distinct filter.

the bug is present in browser and oob applications.