Nothing sticks out as an obvious issue. Here's a possible hazard though:
deg = 360.0 * position / total;
Can total ever be zero? I'm not sure what the arduino does on a divide by zero condition, but you might want to test for it.
Other than that, it's time to pepper your sketch with serial print. Since you're resetting nightly, do you have another arduino with the ability to write to an SD card - might make it easier to gather and save telemetry.