Apparently its a common problem on BMW panoramic sunroofs, the plastic parts go brittle with age and break apart. BMW do sell the parts I need but only in a kit form, cannot buy just the parts I need. Front kit around R3500 and rear kit around R2500 plus the cassette has to be removed, stripped down, replace all the plastic sliders and bits and then re-install the cassette and prey you don't end up with water leaks. Sunroof broke in the vent position, allen key supplied just bends and cannot turn the motor. I have the main glass out until I can fix the damn thing so no more driving it until we can afford to fix it.