my '90 745 seems to have a misaligned drivers window. I found another forum that suggested replacing the window regulator but the regulator was replaced at 225,000 miles in 2014 (I'm at 251,000 now). if I push up on the bottom of the window, it has no problems rolling up and seating properly. any ideas on how to fix this? thanks

 

I believe there's a plastic slider that can get gummed up.

sometimes spraying a dry lube, like T.D.L (from the PB Blaster folks) on the groove the window slides it (along the rear edge of the door) can help.

 

Well, normally this is a sign of a worn regulator but if it was replaced then I'd open it up see what's going on. There is some adjustment that can be made.
All power windows, as a general rule, I never cinch all the way up tight--when warm, the parts expand and plastic breaks over time, metal distorts. I leave them slightly, say 1/8 inch, down from the top, avoids premature wear...