Thanks for the note on track radius. As an aside, I wonder if you could combine the playmobile track with the train-li plastic rails that have been mentioned elsewhere to get more choice in layout.. Obviously the train-li stuff wouldn't match the palymobile connectors, but if you're nailing up down, that should be a big issue.
This layout is looking better and better, really shows how some thought can give a real railway like atmosphere - the track section, point motors etc are probably quite a bit overscale, but together with all the other detailing, they LOOK right.
J.