Could you please give more information about the issue caused by dragging and dropping the docks? The only thing that might be causing problems is the fact that the Width of the control is specified in percents. The RadDock control is designed to be used in fixed layout, and its dimensions should always be specified in pixels. In case you still want to use percents, either of the following solutions should be used:
The problem with the disappearance of the content I believe it is present only when the animations of the control are enabled. Because it takes time for the content to show/hide when expanding/collapsing the dock (with animations enabled), the control cannot correctly calculate the content's and that's why the content disappears. If you think that the users will persistently expand and collapse the dock very quickly, then it is better to disable the animations.
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