LOL! I survived the registry bit...and so did my system! I have tried MA3 on a few other similar systems (Dell, NVIDIA graphics, WinXP & 7) and cannot reproduce the issue. I figured there is something wrong with my M4300, and didn't invest any more time in trying to resolve the shutdown...back to a boring screensaver for now, until this unit is replaced...
Thank you for the advice in troubleshooting!