Today I tried to test this issue, So I installed Navigator 15 (free) and the Dutch OSM maps. I was lucky I knew the way to work with my eyes closed, because I wasn't able to let Navigator show me the way. I set the route the night before, but I wasn't able to get a GPS position. On the way back, I tried the NAVEngine app that did seem to work and after that I switched back to Navigator. then I found this GPS option in one of the Navigator's menu's (the one that has such a small check box that I had to park the car again to check it. After enabling this option I got some dialog box (from Windows 7, I guess) that asked me if I would want to enable this sensor device. After answering this question positive, I was able to watch TV and when I drove away DigiRX told me that the car was moving and the image disappeared: :) ... Navigator showed me my position on the map, but that was all (no instructions).
As I'm not familiar with Navigator, I couldn't find the option to set a route to my home town, I stopped at the next parking along the highway, because trying to find my way through the menu's of this program is not a good idea when driving a car at 130 km/hr... Navigator might be free, but it won't pay for my funeral :(.
After several stops, I finally managed to turn around the route I created last night, but still no instructions and it didn't recalculate the route when I chose an alternative way home. I also found that the indicated speed was always 0.
When I got home (about one and a half hours late), I realized that DigiRx was using the OBDII speed, so all this trouble was quite useless after all: :( again.
Maybe, I'll give it another trial tomorrow after some practicing at home.
It might be my leak of experience with this program, but I really learned to respect navigation programs like TomTom and Sygic after using Navigator for one day!