I have running into very similar issues getting my windows off for the summer. I broke one stud off last night and I am waiting on the PB Blaster to loosen another stud.

I don't seem to be able to get the door top off either and I am nervous about damaging the door.
Is the window top stud sticking in the door bottom shaft, or are the top and bottom stuck together at the seal or both?

Any tips on getting the two halves apart with out damaging them? Can I tap on the studs with a hammer?