If you don't mind shipping to Australia, I would be happy to test for you. I've had other US based companies send me plasma parts for testing and development (and they have done quite well in sales afterwards). I have a 4x4' table and a Thermal Dynamics A120 120 amp machine controlled by Linuxcnc. I have it configured with a 30:1 divider but could change that to 50:1 as it will spike over 10v on piercing. My current controller supports normal up/down THC signals but if necessary, I could build a custom config to suit your THC. And yes, happy to add a relay to enable your THC. A sheetcam post processor would be welcomed. Just be warned that it will be a warts and all report good or bad from a very experienced plasma cutter who has also delved into THC Internals. If you are not 100% confident in you product then send it to someone else who is not familiar with THC functions.