I haven't played with Roadmap in some time, but ISTR that it did its own routing, which is certainly possible with vector maps. There should be no reason for downloading routes if they are used, that's only strictly necessary with raster maps, but the app has to have the routing algorithms programmed into it. I may be mistaken about Roadmap having it, but I know that one app I used did routing. Maybe Roadnav or something like that. I've pretty much given up on mapping on the NIT except for Maemo Mapper since I have a standalone mapping GPS. I use Maemo Mapper just to see the photos, not for routing, and that only occasionally.