It is not possible to navigate between ContextMenu items with the arrow keys when the Keyboard support is enabled.

The ThreeView remains the focused element even after the ContextMenu is shown and using the arrow keys navigates through the tree nodes instead of the ContextMenu items.

Steps to reproduce.

1. Click somewhere on the page and press "F" for focus FileExplorer
   
2. Press "T" to focus TreeView
3. Press "C" to show tree context menu
4. Pres Up/down arrow to navigate through the context menu items

Result: The navigation occurs in the three instead of the Context menu

            <telerik:RadFileExplorer ID="RadFileExplorer1" Height="380px" Width="750px"
                AllowPaging="false" EnableCopy="true" runat="server">
                <Configuration EnableAsyncUpload="true" SearchPatterns="*.*" UploadPaths="~/Images/" DeletePaths="~/Images/" ViewPaths="~/Images/"></Configuration>
            <KeyboardShortcuts
                FocusFileExplorer="F"
                FocusAddressBar="A"
                FocusToolBar="B"
                FocusTreeView="T"
                ContextMenu="C"  
                />