Thanks for all the replies its really helpful, the airbag was replaced and the airbag light came up when I started the car in their driveway. They said it was a clock spring which they charged me $1000 to replace.
When they did the clockspring (on another day) I drove the car for about 20mins and then the lights came up (3 of them) which they are now telling me is the DSC module.
There were no lights prior to either the times they had the vehicle and they said they have reprogrammed the car etc with the clock spring. Could they have shorted the DSC or something?
It is a large Auckland BMW Dealership who've got the vehicle. The car is mobile and the brakes are working fine (at least they were when I drove back with the new set of lights on the same day.
Thanks for all your help.