Well, all the sensors as still running YEAH YEAH YEAH... I think this problem is finally behind me. We have not locked up since moving to the latest versions of the DallasTemperature and OneWire libraries. Not sure what the differences are between the MySensor download versions and the latest, but it appears that was indeed the cause. Is there any way the MySensor project download can be updated to include the latest version of these libraries? Thanks to all who gave suggestions and time in helping me sort this out. I was very close to throwing in the towel..