i ve managed to get some results working a bit with lightburn. i also noticed ( i have read it already) that both lightburn and laserweb can connect to the duet3d . I didn't try to control the the machine through them . i am using the web interface at the moment.
IMG_20220305_104819024.jpg
the upper right one is the clearest one but it still needs some more tweaking.
i am using both of the pwm fans output to control the laser ( FAN0) and the exhaust fan (FAN1) and the workaround for the second fan is to replace the M8 M9 from Lightburn to M106 P1 S1 or S0