I certainly can and will help anyway i can. but my setup using usbcnc is wasted money for you. I happen to have those fancy parts because of my previous cnc which was such a failure and money pit (mydiycnc) that I tried to fix by buying better and better parts. An auduino is perfectly good for a controller and will allow you to control a laser just as much as a router. Just use the heat bed relay for one and the hotend relay for the other. Then hook an appropriate large relay to whichever one and use that to turn router or laser on and off.
The laser was from mydiycnc but it’s just a repackage from photonics something or other i forget.
The trick I use for gcode is simple but maybe slow idk. I just search the gcode text file produced for my router and replace any negative z codes ( down movements) with laser relay on code, and then all positive z codes with laser off. Sounds dumb but works so far. If I had a big fancy laser and did thick or complex things I would probably have to do something else.