Never polish or wax the frozen gray paint as it could lead to a glossy surface.
If washing your frozen gray M3 in a automatic car wash, choose a car wash that does not apply vehicle wax. Rinse the M3 with high pressure water to remove dirt before sending it through the automatic car wash to avoid scratches from sand, dust and other micro-particles.
Remove bugs, bird poo, tree sap, tar, fuel spills or oil immediately using a soft sponge.
Avoid strong rubbing while cleaning the frozen paint. BMW sells suitable products for maintaining the frozen paint at your local dealer.
Repairs to the paint (scratches, dents, etching) must be completed by a BMW trained body shop. Most auto body shop will not be capable of repairing the frozen gray paint.