I really want to assist you on your case. But to do that I need to reproduce the exception on our side because you are the first one reporting such issue. I tried to reproduce it by creating a project following the MVVM approach. This project hosted over 3000 shapes and 2000 links and the exception was not reproduced. This makes me think that the cause of the issue is not the number of the hosted items. It should be something else. But to trace it I will need a simplified project reproducing the exception.
This is why I would like to kindly ask you to try to isolate the issue in a project and send it to us.
Pavel R. Pavlov
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