Looks really good Gordon! Plenty of stuff going on to keep people entertained.
Which shuttle mechanism did you use? I want one and am looking at the LGB ones on eBay but there are a bunch of different versions. Are you using simulated braking?
I was using the simple Playmobil version, so no braking effect and the timing of the stops at either end are anyone's guess. I did a few counts and at one end it was 3 to 4 seconds and at the other 10 or 11. With the same unit, I have had stops of 15-17 seconds.
I have another Playmobil unit which I haven't tried yet and a couple of LGB ones with acceleration and braking, but again I haven't had chance to try them out yet.