Page layout lost after saving a notation

Ok, I played around a little.
I was thinking, because these were all files written with older versions, I tried to copy the score and started a new file with new from clippboard.

But the problem occured again:
BUT not in one part (if you open new attachment it´s "Chor & Bass")
This part let´s me save layout, the others are quite stubborn and don´t allow changes in layout most of the time - but: sometimes there was a change.
Strange.......

I hope you can fix this problem.
Strange that we are the only one, having those problems.

Cheers, Heiko