Before you do anything : make a proper backup using Windows Explorer - and not Home!
The latest map version is 845 ,you could use the 845.2662 with your current Navcore.
However for the full featured 845.2661 map with IQ routes ,Alg and so on you need at least Navcore version 8.2
Tutorials ,map(s) and Keygens can be found in the forum in my threads.
If you need a pssword for my files :
downunder
Bookmarks