I have the same tailgate issue. You basically have to slam the lower tailgate closed each time or the button won't work to close the top half.
I've taken it in 3 times for this two times I've gotten back functioning normally can't duplicate.

The last time I demonstrated the problem to the SA. When I got the car back they said they lubed and adjusted the latch.

The problem is still there.

Beware of the re-flash. My X was re-flashed to sol e some electronic gremlins.
The dealer bricked my car and it took they and BMW two weeks to figure out what happened and how to fix it.

I finally got the latest and greatest software and for the most part every works. BUT it seems that my gas mileage has decreased a lot; not sure I'd it has anything to do with the re-flash but it's odd it happened right at that time.