FWIW: I just went through a similar problem, except that all three lights were yellow.

However, sometimes when I would connect the BMW Scanner, and read the errors, the Brake light would go to red for a few seconds and then go back to yellow. I also had an EML light.

Anyhow, long story short: All these issues were fixed with the following:

1. OEM MAF (I tried an off-brand one and it was making the car do crazy stuff) --- I imagine this is not related to your issue
2. All new gaskets in the intake -- I would imagine this is not related to your issue
3. New decent quality ABS sensors all around.
4. Resetting the wheel angle/level sensor. I reset it using BMW Scanner and also disconnected the car battery for a few minutes. After the battery was connected I did the following juju: open the sunroof by pressing upwards on the sunroof button, turn on the car, turn the wheel all the way to the right and then all the way to the left.

I have been driving it for about 150 miles so far and (cross my fingers, knock on wood) the lights have not come back.

Good luck!