From Auran's Content Creation Art Source:
The in-game crossing rebuilt into UMxing-U451Lt.
UM = U Make your own crossing with your favorite lights, signs, fences, etc.
U = For use with in-game USA, UK and similar roads.
45L = Road angle 45 degree to the left.
1t = 1 track.
Surveyor: Objectmode-NL-Trackside.