At the moment i am in the process of trying to create an Activity Generator Template, for the GN Hi-Line v3.
Am i correct in thinking that in simple terms, all i need to create in AE, is a player path ( starting & finishing in sidings ), in this case Whitefish & Havre.
An AI path starting and finishing in the same locations, but running in the opposite direction.
Plus freight cars of a suitable type placed in each siding along the route ( one in each siding ), with a Pick Up action for each car.
Then from this use AG to do the rest.
Cheers,
Mike.