Eric,
I know this is kinda an old post and I tried to follow your thread on electro-tech-online where you sorted the polarity and finally got it working.
Simple switch on/off circuit help needed. | Electronics Forum (Circuits, Projects and Microcontrollers)
What pins did you end up using on the panel connector? Pins 2 and 6 I understand are +24V and GND. Does the LED in the probe sink enough to register the touch? What about pins 4 and 5?
I'm trying to get something similar working on my TC3.