Hello folks, I'm new to the NAV, just got a 2004 X5 w/ NAV.

Looks like I have the MK4 and I have missing pixels on the screen,

I have some questions, any help is greatly appreciated:

1. Where is the cheapest (incl Free) that I can get a newer DVD (I have 2004-2)

2. How or where can I upgrade or fix my screen?

3. Can I change the cassette player to a CD player behind the screen?

4. Is there software upgrades I can do to the system?

Any other info is greatly appreciated... Thanks