well, had a go @ the little plastic bleeder screw for the heatercore. kinda meh outcome..
 

not the best, but not the worst either. It didn't unscrew at all but rather, after a little bit of resistance/tension, spun in place. I take this to be like the same situation as with my 90, being that the threads have stripped inside their little hole. The good news is that a) the plastic shank didn't twist itself off [as what happened the second time in my 90] and b) the seal isn't loose enough at that point to weep coolant. So if it's gonna be messed up at least it's screwed in a way that doesn't prevent me from operating the car.

I really hate that screw..considering it's an Audi it's such a poor design.