Hi Rick,
Making a generic post processor capability doesn’t sound easy. That is why I suggested that in Lightburn to “copy” the “StartGCode” feature and “apply” it ideally before and after the “laser ON” command (M106 on Marlin) would be so much easier.
This would solve the laser/plasma delay problem with anyone with Marlin firmware (MPCNC, 3D printer with diode laser, etc).
I believe with this mod Lightburn would be the best software for 2D cut processes (laser, plasma or Dknife) in the huge Marlin community. Which would also mean more potential sales for you.