I recently bought RailClone Pro and am starting to use it. (I think it's great!).
I have a road scene and I am using the default traffic cones at 100ft spacing (segment padding 50, 50). The roadway spline is very simple and straight with a couple of hills. When I make my railclone of traffic cones, for the most part they are fine but in a couple of spots the cones don't precisely follow the spline and are slightly below grade (see attached image).
I can fix this by converting the railclone to mesh and moving them manually. The only thing I can think of is that the road spline is very long (several miles) and maybe this scale is causing this?