So I finally ordered the part to repair the rear window on the BMW. I don't know if I'm supposed to be upset that they made a plastic part that can fail so easily, or be impressed by the fact that they made a weak link in the system that can break and be replaced for roughly 50 bucks as opposed to putting direct strain on something expensive like the regulator. Either way, I am again happy that I am a person who is not afraid to work on cars because I can imagine the repair bill for something like this which is really a simple job.