Blimey. That's high. I have genuine CSLs and they are fine at about 32 - 34 psi. Only my opinion of course. I would ask on the CSL Register mate for a definitive answer.
BMW recommended pressures for upto four people in the car, running 225/40 19 front is 33 PSi, rear running 255/35 19 is 35 PSi, I don't see why running CSL reps would drastically alter the pressures.
