Roads and especially railways are "Not accurate for aeronautical use" - stated by SD.
Suppose it will take some time while SD will fix this issue with the supplier of above data (if solved at all due to the volume of work).
As SD is a VFR moving map I would appreciate a layer that is really important in eyeball navigation - highways including junctions (polylines instead of easy to digest lines).
I suggest to put ACCURATE highways into a separate layer. In that way the inaccuracy of roads could be solved partly with reasonable efforts.
Real highway centerline coordinates can be obtained more easily then all kind of road data.
Joseph