CNCAdmin
The only reason (ever) a OneCNC demo will not run after proper install is due to a video card driver that has an issue with OpenGL (We are OpenGL certified) in their driver or its the wrong driver/out of date driver.
A great way of determing video card driver conflicts is to boot your computer in safe mode (Windows loads only their generic "default" drivers.) The demo should now run, and if so, its time to hunt down new drivers for that card.
Tech Support
OneCNC LL
(877) 626-1262
www.onecnc.com