Decided to move it into the workshop and see if it will talk to the windows 7 machine (this one is still on xp) which should have all the drivers already installed. I think the laser engraver has an atmega 2560 chip - and I can definitely talk to that.
Also easier for printing mods, and saves me sticking a new battery in the digital calipers on this desk :-)

Less space to work - but the machine is actually smaller than I was expecting.