Hi all!

I have a 2003 E46 with MK IV and 4-1/12 (yes I know... ), and I just recently became aware of the possibility of upgrading the FW(?) of the Nav.

I would greatly appreciate it if someone could help me understand a few things:

1) What is the difference between FW, OS and SIB?
2) Do I need to update in a specific order? (via V20-something before V31/V32?)
3) Would the V32 be the best choice for my system?
4) I think my Map DVD is from 2002/2004 or something.., how do I get the newest most updated maps for my region? (Europe/Scandinavia)

Again, I would probably learn all this by reading all the threads and the thousands of posts in the forum, but I hope some kind expert would guide me in the right direction...