Hey lilix1, sounds like you are doing a timing chain job? If you are, I attached a nice walk-through post. It is based on the FCP Euro videos with specifics for the AWD cars. I used it for my 2013 N20 xdrive, pretty straightforward.
Unfortunately it doesn't mention a specific torque spec for the front diff mount bolts but I'd say at least 30 ft-lbs is needed. Use judgement, tighten everything equally before stepping up the torque, and you won't strip a bolt.
For the engine supports, why are you removing them? Is the engine coming out of the car? I found it's necessary to drop the subframe in order to move the diff and remove the oil pan.
https://www.bimmerfest.com/threads/n...n-diy.1395027/