This issue could be caused if you have upgrated your binaries from Q2 2014 or below to our latest binaries and you are having a custom style targeting RadDiagramShape and it is not based on to the default one. With our previous version of binaries the RenderTransformOrigin property of the RadDiagramShape was set in the constructor to (0.5 0.5). However with our latest binaries that logic is placed inside the default RadDiagramShape Style and it is removed from the constructor. That is why if you have a custom style targeting the RadDiagramShape and it is not based on the default one the RenderTransformOrigin will be (0 0), setting that property to (0.5 0.5) will fix the issue.
if that is not the case, please give us a sample project in which we could reproduce the issue, so we could further investigate the issue.
Looking forward to hearing from you.
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