I had one of these in my JCUT CNC machine. Drivers failed to load (yellow) I tried on multiple machines and found one that would work. Even with the driver loaded it would not interface with the cnc. This could have been in part due to the non-existant setup instructions for pin config or any other interface instructions. I finally gave up, Installed a Smooth stepper interface and new break out board and everything works great!. I would ditch the JNC-40m and buy the smooth stepper for about the same price and with it you get GREAT support!
my two bits.....months in the learning.