Ah, well for starters, nothing gets saved other than position and altitude on a Saved flight. Everything is reset, and I mean everything. If you were at a high enough altitude for example, everything would have been frozen over even if you had left it with a clear windshield and the heater running full blast.
Saved flights are…problematic. Saved state is actually a Wishlist item somewhere that you can participate in (and vote on as you see fit).
As for the rest of it - type plane and were you using a modified version of the Navigation Unit?