Very nice. Darstaed and ACE were partners at one time, as far as I understand it. Check to make sure that there isn’t / wasn’t some sort of tensioner piece of something that held the window inserts taught vs. glue. Regarding the bubbling of the detail strip... that is an issue as far back as the Darphin replicas. I have some spots of it on one of my Rheingold coaches and I’ve seen it on others. I have no solution to recommend.
Kind regards, Chris