I can see that you are using outdated version of our binaries. I tried to reproduce the reported behavior in our QSF with our latest official release and it seems that the code works as expected. Could you please upgrade your binaries and test the same scenario on your side?
Regarding your second requirement, I suppose that you created the little rectangle in the ContentTemplate of the RadDiagramShape. I can tell that because the RadDiagram applies rotate transformation to the rotated shape. This means the content of the rotated shape will be rotated as one part and this is the designed and expected behavior. Unfortunately, there is no way to achieve the required behavior out of the box.
Pavel R. Pavlov
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