There is a solder bridge for that relay that links it to an output that can be controlled by UCCNC.
There's a solder bridge that optionally has the charge pump activate the relay, is that what you are talking about?
By default, all 3 relays are controlled by outputs.



Since it wasn't being used, and I need a switch for the OSSD override, I just wired my OSSD override into the normally open side of that relay and mapped an output trigger linked to the "override limits" software button found on the main screen of UCCNC.
So, you have a wire from SafetyOVR to NO3, and from CM3 to 0V?

Do you have the Output Trigger mapped to LED 27, and set to Port 3, Pin 17?

Here's the issue I think.
1) If you actually hit a limit, until you jog off the limit, the OSSD output will keep triggering the Reset, so you kinda have a loop where it Overrides it, but then it instantly gets tripped again.
2) The Limit override only stays on while a limit is triggered. If you use an Estop, you can't turn on the limit override.

What I would try, is to use a macroloop, and a custom LED. I don't know the specifics of your setup to go into more detail. But you'd have the macroloop turn on when the limit or estop is hit, Have the output triggered by the state of the custom LED.