The reset sequence for iDrive: press the 2 eject buttons (CD + DVD) AND the volume knob in... hold it for a few secs.
Mine froze up during the 1st month of having it, did the reset, and ever since then it never did that again.
*edit: I believe any s/w diagnosis/updates are all done via the OBD-2 port which is located somewhat above the hood release lever. So you might feel bypassing is ok and removing any install traces (ground wire maybe) or completely removing to have a peace of mind. My understanding is they'll run diagnostic checks and it may or may not find anything abnormal. But I'm sure others are more qualified to chime in having taken their's in with it installed.
335i E90 / Arctic / Gray / Burl Walnut / Steptronic / ZPP / ZSP / Paddles / CA / Nav / PDC / OEM Spoiler
Mods: PIAA Angel Eyes, Rear Fog Switch, Escort X50 Blue hardwire, 30% Charcoal Llumar
Installing soon: Rear Power Outlets (Happy Robot mod!)