We are aware of this issue. You are not doing anything wrong. The problem is put in our high-priority list for resolution and will be fixed for the next distribution. The entity diagram is not updated properly. Since the generated code is fine you should not experience any problems when working with the domain model.
Thanks again for the valuable input. Do not hesitate to contact us again, should you find anything troubling or you need any assistance.
the Telerik team
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