When RadDocking saves its layout, it doesn't persists the value of the bound properties. For example, if the RadPane.IsHidden property is bound, it doesn't persists its value in the xml in order to not break the binding when loading. However, if a property is not bound but set, it's expected to save the object as string in the xml and load its value later. Can you try to bind the Header/Title property of the pane?
Hope this helps.
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