Almost all K40s can now be used with lightburn without replacing the motherboard, thanks to @Tatarize’s Meerk40t
MeerK40t can pretend to be a Ruida controller and translate to other kinds of control boards that have shipped with K40s like M2 Nano, the old Moshiboard controllers, and now the new M3 Nano. Lightburn is configured to talk to a Ruida controller and pointed at MeerK40t, which understands the Ruida protocol and translates it for the other controllers.