Then take the time and start reading ... much. You have more material on this forum than you need
Install some good file manager - TTC, X-Plorer...
Uninstall that iGO completely. Wipe all the tails behind him (in root and in android/data)
Download any NexxtGen you like (I suggest iGO Pal), download the latest maps from the appropriate section, the last global_cfg...put all to card...
[Only registered and activated users can see links. ]
transfer from card to internal memory.
Follow the basic instructions, install it, grant all necessary permissions and enjoy

On the other hand you can install any other software - Sygic, TomTom NDS...
Or you can have all of them in the unit together.