First we started some research with sculpt and phisical trolley, but the result wasn't the best. The old HAVOK engine is not enough for this. The next experiment was about smoothing the movement of nonphys vehicle. The prim limit was about 30 prim, the owner wanted to keep low prim as possible.
After one week the system was ready, and almost all primworks and unique textures too. Laying track, and put on the Trolleys took another day, and some more for the service car.
The common Trolley is driven by an Automaton, who inform about next station, and the stop and start of the trolley.
Well, the Trolley still runs, anyone may travell on the line in Steeltopia, or check the mini model in our factory at SOL Solution Island.