update: i've just borrowed a 2003 oem dvd from a friend and it works! before this i've tried a 2004 oem dvd and it didnt work so i assumed it was the drive, but now i think it must be that its so sensitive it will even reject some oem discs!

friend doesn't use nav much so is giving me his disc, my copies work in his drive so i gave him one of mine.
now we both have nav!
wahey!...........still think its abit naff that the bmw navs are so sensitive..

anyway....CHEERS!