Issue Resolved.
Doing a little more troubleshooting, I found that this scaling issue only existed on my CNC PC, running mach in demo on my notebook pc, the displace was correct,
tried a different monitor, no change, updated intel 530 graphic card driver, no change..
display resolution in windows 10 on both cnc pc and notebook are both 1920x1080 DPI set to 96dpi on both and the mach screen was also designed with 1920x1080 resolution.
I tried a registry hack that allowed me to tweak the dpi setting slightly I changed from 96 to 98 dpi and the scaling issue was corrected.
I am posting the regedit procedure in case anyone else runs into this.
Bob