BMW's Suggestions to avoid paint damage -
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 (you should be killed) 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.
The agreement goes on to explicitly state that the warranty does not cover the frozen gray paint if it is damage by the owner as a result of negligence, lack of maintenance or proper care, environmental damage or improper repairs.
Only once the agreement is signed and returned to BMW will their car be shipped to them. Without signing the notice you're not getting your shiny new (or in this case matt) 2011 BMW Frozen Gray M3.