Most co2 lasers fail to lase around the 10% level. Yours is just a bit higher.
The configuration is the allowed pwm range and the controller will never go below the min or above the max… You appear to have both set that will allow maximum levels.
I think you will have to live with the 12% as the bottom end for that tube.
IMHO, I would set the controllers laser power minimum to 12%. It protects the tube from lower pwm levels that could damage the tube.
Sorry to burst your bubble, but the power percentage is a fantasy number. It’s composed of the laser tube, the laser PSU, and the controller. Change any one or more of them and it goes out the window. A similar laser will be similar, but never the same.
All CO2 lasers have a minimum firing threshold. The larger / higher power, the higher that threshold is. It is a physical thing, not a software thing. There is absolutely nothing you can do about it.
Dropping below that for an input won’t do anything but not fire the tube. Part of my power test involves a 1% line to give me time to get the sensor in place before it actually fires.
The Ruida loads the complete file. Lightburn has no idea at what part of if the machine is even running. Unlike a grbl that the codes are sent in a serial fashion.