Yes you can't move the RadDiagramShapes using the Visual Studio's designer but you can do this using their Position property:
This is a really strange exception and unfortunately we weren't able to reproduce it. Please note that the RadDiagram needs the Telerik.Windows.Diagrams.Core
too so could you please try to add it and test again ? I tested this scenario with Visual Studio 2013 version 12.0.21005.1 and Telerik dlls version 2013.3.1316.45.
We're looking forward to hearing from you again.
p.s. One more question - are you using our installers/msi or the zip files with the dlls ?
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