I have a N95 too, and it's too slow to work well as a primary GPS unit (great as a backup, or on a rental car). Generating a route takes quite a bit of time (30-60 seconds?) when I tested it.
Anyways, I'd imagine what you can do if you really want to, is have a RCA video input on your carpc where the N95 feeds into. Then when you hit the GPS button in RR, it's pulls up the video input in a window. For controls, you might want to try python. There's an interesting link
here about using a module called LocationRequestor to access the internal GPS.