I just took it in ..
- the control module appeared to be fine
- the gears appeared to be fine
- the motor appeared to work fine
After looking at it for 3-4 hours they threw in a new motor and it worked like a charm .. probably misaligned gears. In the end, I decided that it was cheaper just to throw a new motor in there, especially because they reduced the 4 hour charge to under an hour of labour ;-) ...
I'm just glad it works now.