When I had my Bluetooth issue rectified, they had to re Flash the car to configure the unit to the car and it took 4 hours just to do that. It also changed a number of the defaults I had set on the car which meant I had to re-program them manually.
With the MOST bus system, it appears that every unit in the car has an identity and that identity has to be recognised by the central control unit before it will operate. This would indicate that any repair work when the car is out of warrenty means it has to go back to the dealer to program. Gaurenteed trailler business for BMW dealers. No wonder they are all building bigger and better service workshops as they are going to need them with the flood of people expected in the years to come.