Ok Doug, here goes. I posted sunroof fixerupper procedures some time ago and they actually made it into the 700/900 FAQ section. I'm honored! Anyway, to make corrections, slide the insert back by pulling down on the rear of the headliner, by the light. Slide the sunroof insert back into the roof, but not too far. VIOLA, the guts are exposed, so check out its operation, ie flip it up in back, operate it normally. Be VERY careful or you will loose the insert into the bowles of the headliner never to be found again. Once checked, the screws can be tightened and the height adjusted. The little metal slides are called 'control mechanisms' in the VOLVO repair manuals and they can break. If broken, see the procedures in the 700/900 FAQ section. You might also lube the sliding parts of the control mechanisms.

Good luck and keep us up to date on your results.

BTW, it's not as hard as you might think.

BTW2, I personally prefer the 'bud man, volvo fan' moniker!