Jason Petho - Trains query re Matrix

[Glint]

Hi Jason,
Firstly, many thanks to you and the team for such a grand update. Having looked through a fair bit now, I am in awe of all the work that has been done.
Can you tell me how I get rail supply carriages to move? I have various trains and carriages in a scenario I'm putting together but can't find a way of getting the supply carriages to run?
Also, I didn't notice anything in the manual describing how to use the trains and carriages? Maybe I'm dense, lol, but your assistance would be appreciated.
regards
Peter