Your switch arrived today. The problem is that it has a (to me) unnecessary diode connecting to the TIP switch. I case see no reason for it to be there, as there is not one in the RNG switch (this is why RNG works). I'm guessing it was for the convenience of the wireman.

All diodes in the switch cause a voltage drop of around 0.6V – the software allows for this in the T+R case (where diodes are necessary) but does not allow for it in T or R.

We'll change the software for the next release in case other people have switches like this. In the meantime the answer is to short out the diode. Let me know if you want me to do this before I send the switch back.