In Reply to: 525i headliner, inside door panels detaching posted by Kiwidog on September 14, 1999 at 21:09:05:
*Lots* of postings about these issues. If you check the archives, there are pretty good ways to correct the door panel problem by removing the stick-on panel, slitting the vinyl, re-gluing it to the door board and reattaching the stick-on panel. You can search around and see what you can find.
I think the consensus on the headliner is pretty much to resign yourself to replacement. Not cheap, but prettier than trying to glue it yourself. I personally have experience with 3M's high-tack spray-on adhesive for this purpose, but the results aren't fitting of a bimmer (maybe its poor technique rather than poor adhesive in my case ;)