I recently purchased the new tri-Power CNC, which comes with the MACH III software. I'm using BobCad/CAM software to produce drawings and generate the G-code, no problem there. the Tri-power uses the parallel port on the computer to control the CNC processors on the machine and BobCad uses the RS-232. In order to get the machine running you have to save the bobCad file and then import it into the MACH III, no problem there. I generated a small program to do some milling and then loaded into Mach III and received the following message, "F word missing with inverse time arc move on line number #5". I contacted bobCad support and they had me send the program to them and they got it to run with no problems. I'm waiting for Camtronics in seattle to open so that I can call them, but though maybe someone could help in the mean time.