actully my X5 is US made and i found that if i press and hold all windows would open, and that to close them all u just insert the key in the door, and press and hold to the left or right i dont remember but then all open windows will be closed
regarding the PDC, mmmmm ya u r right, y do i need it on all the time but my friend has a 07 Merceds E240 and the PDC is on all the time then i though also mine could have the same option but without it i can survive