Wouldn't be surprised if I ran into some decision limit; it was for the Empty the Supply in 1 Turn puzzle. No big deal if it's not fixable, just wanted to let you know.
It is known that some games can't be loaded, but unfortunately not why. Previous cases invloved Black Market and Smugglers I think, but those are all fixed now.
I don't think there's anything particularly complicated involved with the cards (nothing like the Overlord/Pixie/Lurker/King's Court loop, for example). Just length, cards gained and trashed - every buy took a Travelling Fair, almost everything was trashed, and a lot of Advance as well with Fortress coming back to hand. Lots of while-in-play effects (10 Priests and Bridge Trolls). Maybe the coins generated (I ended the game with over $3000 left).
But I didn't get a screenshot before my turn ended and it cleaned up. I had 4 Fortresses, and Watchtower, and all the Colonies in hand, all the Platinums in my deck, and all the other victory cards in my discard. Tons of cards in play (all the other Fortresses, the Villas, Priests, and Bridge Trolls, a Watchtower, my starting Treasure). Everything else in the trash.