Her står det forklart for E36:
* (snowflake) was the Winter setting which locked out 1st gear to avoid excessive wheelspin in the snow (and might even have brought the auto upshift point further down the rev range than E)
The snow setting allows you to manually set the gear e.g if you choose snow, then put the auto box in 3rd gear, it will stay in 3rd gear until changed. This can be useful for low traction situations, as you can keep the revs down. You listed the third setting as being M? on mine it was a snowflake.
Det du mener med at den ligger lavere på turtall er at du låser den fra å gire ned, antar jeg...