In Germany construction on highways often leads to changeing of sides on the Autobahn. Navigator recalculates the route and says "no route found". The navigation is finished and there is no way to continue. I have to kill the app. The same may happen with a parking place along a highway or national road. I'm using OSM maps but don't think it is related. Navigator reculcates the route just too often although I like it very much that it tells when it does.
The message in the middle of navigation was a mistake in 1.1.5. It is removed from 1.2.19+ and it should behave similarly as in older versions. There should be improved GPS snap if you are using Car profile ... let us know if it is better. Here is the direct download link: http://download.mapfactor.com/mapfactor_navigator.apk