Take a look at the photo-etched brass deck: it became deformed like that overnight...
I can only attribute it to the changes in temperature as I think it was actually well glued with Cyanolit (green tube). The solution? Cover it with Dass clay. And it's not the first time something like this happens..
I don't have a lot of experience with PE parts but glueing the deck is a pretty straightforward process, it's just a flat part that wasn't even subjected to any tension, I thought it would just sit there unaltered for the whole modeling eternity with a coat of CA glue bonding it to the plastic part.