Someone asked if it was possible to use GoDiagram in a C++ / MFC application. I was pretty sure it was, but just to be sure, I did the following:
Following the directions on How to: Create the User Control and Host MDI View | Microsoft Learn, and using a very simple GoDiagram based UserControl I had created earlier.
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I get the app pictured below (the object is a simple GoRectangle, but you can move it, copy it, and so on)
Note this is just a UserControl plugged into an MFC application. There is no interaction from the C++ code with the diagram in this example.