well... i got the car back. the dealer was great about it, and did a lot to try to fix the problems. they added foam to the roof in some spots and replaced the passenger window motor again.
unfortunately, the roof rattles exactly as it always did, and after one day, the passenger window began misbehaving. after 3 days now, the passenger window is completely defiant and will not stay closed. tomorrow i'll report back to bmw na, who i informed of these ongoing issues just prior to the warranty expiring. bmw na refused to promise any kind of extended coverage at that time, but told me they usually will agree to continue to cover the problem issues if a post-warranty inspection shows the issues remain. hopefully bmw will agree to extend coverage at least to these items. maybe that will be what it takes to finally get these problems fixed.