1. Use the Helpdesk link above and follow the instructions.
2. Wait for N3V to find this thread and reply accordingly (it's likely to be WindWalkr or pw3r that responds).
IF I understand your question correctly, I'd have to agree with Shane, and say YES also.
--The RailDriver unit is an example of a working interface, so on some level, it should be possible to have a "custom" controller, again, IF I understand your question correctly.
I have a whole bunch of custom hardware that I want to I/O to Trainz. For example I envision having a hardware like throttle controller over RS232 listen on a port to that and convert to messages like SetThrottle(50) for example. I may have to write some middleware that listens to the ports and converts to some message format Trainz understands. That sort of thing. I will look at RailDriver unit see what it does.