Quote Originally Posted by A_Camera View Post
I think more details are needed... Some Chinese USB motion controllers are pure crap, support only a limited number of G-code commands. Typically watch out with probing (G31) because most didn't implement it at all or implemented incorrectly. Some even pirated other brand, but because they didn't manage to make 100% copies, the original software is not working with them. Unfortunately now that you have the machine you are stuck. Byte the bullet and pay the price of asking questions too late... Of course, I can be wrong, but the lack of support from the seller indicates that he sold you pirated software or hardware or both, or just a demo version of a software (which software are you using?). Maybe you have to change the hardware as well, so post more details, perhaps someone can help.
If the machine he bought came with USB, do you think he could just try installing Mach3 for controlling is machine? I never used Mach3 with USB, only parallel port.