I already answered this question in your support thread, but I will copy paste the same answer here so that others from the community can find it. Hopefully it will help others too.
Thank you for contacting us on that matter. I am happy to inform you that the RadDiagram framework exposes extensibility points of its default tools, such as the PanningTool and the PointerTool. In your particular scenario you can take advantage of those extensibility points. You can create custom behavior of those tools whenever user clicks with the right mouse button.
For your convenience we prepared a sample project that can be use as starting point. Please take a look at it and let us know if you need any further assistance.
Pavel R. Pavlov
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