Barrylevine, your trip could be classified as a bit of a nailbiter and glad you made it home without having to push the car. To answer your question, I don't think it' a gauge calibration issue, but perhaps others have some ideas...
How about some external factors:
1. Ambient temperature (even though you did not run the heater)
2. Headwind (this is often a sleeper)
3. Not paying attention during the first part of the trip and then very belatedly realizing that perhaps a bit of hypermiling was needed to get home
4. Rain or snow
5. Tire pressure
When you started your trip, do you remember your RR?
After your return, recharging gave you what RR?
In any case, if you fully fully recharged after that turtle experience then your system probably recalibrated itself. Always fun to check things with EVBatMon (capacity) and CaniOn (cell balance) when you're at extremes.
Good luck, and let us know how you do on this same trip in the future.
BTW, whereabouts are you located?
http://myimiev.com/forum/viewtopic.php?f=13&t=3196
