Do you have a crash-dump?

no...
it's like a buffer overflow... showing only in the bottom part of the image screen...

I've seen a line about BlockContext...

Do you have block-contexts or MADynamicObject instances in your
serialized mode? If you do, you have to get rid of them beforehand:

PRComponent allInstancesDo: [ :each | each reset ]

I'll try to make a kernel backup after making that...

Is it:
PRComponent allInstancesDo: [ :each | each reset ]
or

PRComponent allSubInstancesDo: [ :each | each reset ]

Thanks Lukas