Pins 1 & 2 are for the torch firing wires and it doesn’t matter which wire goes to which pin, they are just closing a circuit to command the torch to fire.
Pins 4 & 6 are the divided voltage pins, with 6 being the positive. The wires that Langmuir provides for the divided voltage use the black wire to positive and the red to negative.
Everlast machines come from the factory with the divided voltage set at 16:1, so you have to remove a jumper from the board to change it to the 50:1 that Langmuir requires.
You should also know that there have been issues with the divided voltage and the raw voltage not being correct from the CNC port on the Everlast machines, so some of us have just connected to raw voltage inside the machine to avoid those issues.