Okay. I see how looking in on train control signals can accomplish the same task as having a second sensor. Much more reasonable to have just one sensor per stop. That makes one IRV2 and one sensor add-on package for a total of 4 sensors a very sensible starting setup. Add in your new game module with 4 indicators and a scoreboard and you're in business.
I've got a desktop CO2 laser that could make quick work of clear acrylic, and I'm happy to help with prototyping if you like.
A couple of ideas have crossed my mind on how to indicate a destination. You could have a separate "bank" of lights for each destination, but that could get out of control pretty quick if you've got a large number of stops. Another option would be to use the colors to represent the destination. Like if each indicator had a light on top that could become a unique color, then if you see that color indicated on the board of another station, you'd know where to take that "thing." Perhaps a blinking or pulsing pattern could separate departures from arrivals. Maybe you've got two separate stands for each station, one for departures and one for arrivals. Then you could save color for the type or quantity of things being transported (freight, people, etc.)
Now I need to go get my layout to a minimally functioning state so I can participate! I mentioned that I was excited about it right?
