Playing as Baktria, I laid siege to Kophen, intending to starve them out. With 2 turns to go, it was winter, and I clicked 'end turn'. Reinforcements arrived and attacked me, resulting in an open field battle. My general gave a great speech saying that his army was outnumbered, but of better quality and on the defensive, pointing out their lack of spearmen to confront my cavalry, how even though the omens were bad, the gods were with us, and his men were brave.

Outnumbered, surprised by enemy reinforcements in my rear area, and faced with a superior general, I still managed a heroic victory! The loading screen appeared, and next I would have expected to see the options of what to do with the town. Instead, I got a dreaded CTD.

Posting this now while it's still fresh in my memory. Can't even win the siege on autoresolve, much less this battle, so I'm going to have to play it out again and see if I can replicate it. Another possibility is playing out the siege battle and see what happens then.