Please post your questions here (
http://www.e90post.com/forums/forumdisplay.php?f=368) if you get stuck.
I don't know if this applies to M3s but there are other cool features that I like.
-Disable the safety feature that stops windows from rolling down when your passenger opens their door. Car is off and you're rolling up the windows before you get out of the car. If the passenger opens their door before the windows rolls up completely, it'll stop it in midway.
-Let the wipers complete their cycle when you shut down the car. If you shut down your car while the wiper is in the middle of the windscreen, it will just stay there.
These 2 things bugged the hell out of me before I fixed them through coding.