If your car is supposed to have the feature, I would expect BMW to fix it/code it for you under warranty (with regards to the launch control).
Regarding the brake lights, if they were illegal, it wouldn't matter in a court of law, you would lose. Fortunately, they are not (this is cool) and valid as long as they flash no more than 4 times in 4 seconds.
https://www.dmv.ca.gov/portal/dmv/de.../c2/a7/25251.5