Hi, I'm new with mapfactor free - and mostly happy.
I detected that a 5th level (yellow) city street gets imported as normal street, so that I can't prefer it relating to lower level streets (example: Munich, untermenzinger straße is yellow at www.openstreetmap.org - but I can't prefer it to lower level streets like ohlauer straße which is plain white at osm).
Additionally the street ambosstraße is marked as "eingeschraenkter zugang" (restricted access) at osm - but navigator uses it for routing even if "andere straße" is deactivated - this street is displayed as regular street in navigator map.
So - in both cases osm displays the streets correctly, so that the data base should be OK. So it seems to me like a generic importing problem.
As I see it is just a matter of rendering. Two levels of road types are rendered as white. It doesn't mean, that you can't prefere one to another. Untermenzinger is prefered to Ohlauer even with default setings.