Solidworks 2020 is losing a lot of model information in components working perfectly in 2019.

See attached for example.

Taking the 2019 and dragging directly into 2020 on first appearance looks good, but after a re-build .. many of the model bodies are lost and turn red in the feature tree.

This is happening on many user library components.

Is anyone else seeing this??

Does anyone have a possible solution ??

Our user library is quite extensive and would take hours upon hours of time to resolve everything.

Thank you

Mark