I would suggest using the client-side API (http://www.telerik.com/help/aspnet-ajax/dock-client-raddock.html
) and events (http://www.telerik.com/help/aspnet-ajax/dock-client-side-events.html
) of RadDock to achieve the desired functionality.
If you utilized them and the problem still occurs, please isolate it in a fully runnable project and send it via a support ticket so that I can inspect it locally and provide a more to the point answer.
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