Hi, Marian,
Currently, the possible solution that I can suggest before loading the xml, recreate the RadDiagram control. Thus, any existing elements inside RadDiagram will be eliminated and the layout will be loaded on a brand new diagram.
Please excuse us for the inconvenience caused. We will do our best to introduce a fix in the upcoming releases. Stay tuned.
Regards,
Dess | Tech Support Engineer, Principal
Progress Telerik
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