[Update] I can now say with confidence that returning to the main menu before exiting seems to have taken care of the error that popped up on exit. I've not yet had a repeat of both sides routing at the same time in the detailed battle, so I don't know if that's still a problem for me.

<t> Every time I exit from the game, I get the Plato error. Just yesterday I starting locking up and getting the error when the game tried to switch from detailed combat back to the main part of the game. This has only occurred when the battle resulted in both sides routing. The battle winds down ...