ok man, about the upgrades...
if i use these steps, then nothing can be wrong ?! right..

1. Open driver door
2. Start the engine
3. Go to Menu - Set - (check Firmware Vers.)
4. Chose the new update CD/DVD vers.
5. Insert in DVD Navi in trunk
6. Follow the indication on screen
7. Eject the CD/DVD
8. Press OK
9. Restart

i mean that i can't damage the Navi Unit if i insert the new CD/DVD upgrades.
- i can damage the Navi only if i stop the engine during upgrade process ?
What NOT to do so u can successfully update your Navi.

thanks