West Highland scenario problems

[sparky12345]

Hi all - Im still very much getting to grips with TS2015 so be gentle!

I'm attempting to create a shunting scenario, in free roam, on the Thompson West Highland Extension route. I've got a couple of AI trains, and a class 37 which is what I'd like to drive. However, while I have added a driver, I've not added any instructions, as the scenario involves coupling to recently arrived AI trains etc, which I think causes problems? I'd also quite like to do what I want, in between trains, hence creating a free roam scenario.

The first problem is as follows: Class 37 goes from yard to a red signal, to await the passing of a sleeper. The idea is that the 37 then follows the sleeper into the station, and either couples to the back, or goes into the siding. Once it is clear, a class 156 follows from the yard, to the station, then departs for Mallaig. However, what actually happens is the rote gets set for the 156 following the arrival of the sleeper, and I can't change anything to get out of its way, so I end up with a derailment. Is there a way of doing this so there is no collision? I also have the 156 set to stay in the station for 20 minutes or so. Once it arrives in the platform, the route seems to be locked for it to go to Mallaig - is there any way of being able to override that so I could perhaps move the coaches while the 156 is in the station?

I'm sure adding instructions to the 37 would solve the problem, (ie drive to Fort William station siding), but then once I re-take control of the 37, will it then try to get back to the siding? If I swap to another loco while assembling my train, it would be a huge pain if the 37 decided to trundle back off to the station...

Any help is much appreciated!

Chris

[sparky12345]

I should perhaps of mentioned, the class 37 I'm using is the S&C version, so RETB is not used.