Went to few tyre shops and ask some bmw mechs.....all i can sum up is:-
1) YES, its non adjustable for e46 front camber, but on top of the mounting there are space to adjust by abit if you unscrew it. though it wont help much but its better than nothing
2) its meant to be slanted especially lowered, the only thing can do is rotate ur tyre every 6 months to even it out. just make sure u check as my previous tyres got cracks and holes due to excessive wear in the inner part. (verified by bmw mechs)
3) Third, dont go to che kai tyre shop, go to professional type, its better to be expensive than given the wrong info.....first shop in klang say my lower arm spoil thats why slanted front...second shop in oug famous one check ok ma the lower arm, still new....so go figure.