Interlocking Not Following Map

I am trying to create a scenario for the San Bernardino-Barstow Route. I have been working on this for almost 2 weeks and I keep having the same problem. I have set the route that the player train will take. Set all of its go via points, and end point. At Victorville I have the route point switching the train from track one to track two. On the map it shows that the train will switch from track one to track two. In reality, when I run the route the train does not make the switch, which in turn causes a head on collision with a AI further up the track. I am at my wits end, and about to scatter this scenairo's electrons into computer hell. Has anyone sufferd this kind of problem before, if so, how did you correct it?