Hi Mathias,
Could you please have a look at:
Error-When-Saving-Bounds2DComponent (Serialization error)
It is related to what Max is trying to do too. I am asking you since you mentioned about need of boundingRect property... something I suspect I am doing wrong (any particular flags must be set for it to work, e.g. when using addProp(..) in the BeanInfo?). Any chance you can advice how exactly that property needs to be added and if you aware of anything else needed for such component to be saved?
Thank you.