Very nice mate.

From my experience with BMW. It is best to stick with what BMW say. I went for aftermarket diff oil in a M3 and it made the diff judder. I put the proper BMW oil in and within ten miles it was silent and working fine.

From that day I stuck in what they said. Cost a little bit more but it is the right stuff for the car.

As for the key, sadly with this kind of thing, you need a computer to do the work. My local specialist had to borrow the machine used for keys etc from our local BMW dealer to resolve some issues. Its bloody expensive kit so might be a dealer only unless it is something silly.

I am sure the keys auto charge when in the ignition, maybe the battery is on its last legs or something? hard to explain.

We have never had any problems with our keys. I know you can get some software to run on a laptop that allows you to turn stuff on and off, things like folding mirrors to fold etc when locking, lights flash when alarming the car, windows up and down on the press of a button etc etc loads of stuff. I use E46Zone. Good website, lots of very helpful people and most know how to resolve the bulk of issues.