NavList:

For determining distance, the only thing I can think of is a tortured application of "distance to the horizon," finding features along the edge of the visible disc to determine how much less than 180° of the moon's surface is visible.  The hard part would probably be identifying usable features while viewing them edge-on, but it would let you ignore any image distortions as it'd be a binary "see it/don't see it" process.