ferika: I'm not sure I follow exactly what the issue you are having is. The Navit.xml file that is on the wiki is not set to use the sample map. It is set to look for a map file in "/media/mmc1/map". Place whatever map file you have in that location.

Note that if you are using map data for just your state or country Navit will not have data to draw a world map from. You would need a world map from OSM to do that but note that performance can take a hit and it comes in at 2+GB.

Now... When you start Navit for the first time it doesn't know where it is and where it should center the map. If you are using the sample navit.xml file the default position that Navit is going to go to will be Las Vegas Nevada. If you don't have map data then you will be staring at a beige screen.

IF your map file is indeed loaded correctly then you can either wait for a GPS signal lock at which point Navit should center to your location and you should see your map data. This assumes that the map file you are using has data for the location you are getting a GPS position.

The other option is to do a search for a city known to be within the map data you are using. This is spelled out in the wiki page so refer to it if you don't know how to do it already.

I hope that puts you on the right track.