Turn the DSC off as well. In the snow your wheels are going to want to spin a little on start and other instances. With the DSC on it will not allow the wheels to spin and causes trouble in the snow. When DSC is off it allow the wheels to spin and therefore allowing better snow capabilities. Make sure you only turn off DSC and leave the traction control on.....
P.S. Remember that DSC is on by default. If/when you turn the car off, when you restart the car DSC will automatically be active again. You have to manually turn off DSC every time....
P.S.S. Welcome to the board April! Post photos when you can. We would love to see your BMW.....
*EDIT* fix a sentence stucture and wording to sound correct....