Without going into a lot of detail, the original release of the Northern contained references to files in the Cascadian route. These have been resolved and, rather than issue another patch, I've re-built the locomotive package. The new package has been uploaded to RWA, and it's also temporarily available for immediate download at the G-TraX web site. This time the package files are contained in an RWP archive. It's probably a good idea to delete the existing files (Assets\G-TraX\Preservation).
Once again, detail parts that vanish at long distance do so intentionally as a consequence of the LOD scheme.
Thanks for your patience. Now you know why this is freeware!