I think there used to be a way to disable auto-play in the middle of a game. Is that gone?
There was a game vs Lord Rattington where I had a curse in exile, the pile of curses had only one left in it, and I wanted to buy that curse so I could then discard the one in exile and scrap all of them using Donate. But the autoplay "Keep bad cards in exile" meant I was not able to discard the existing one from exile. I didn't see any way to disable that anywhere, short of resigning the game and doing it in the main site. But if I resigned the game there'd be no point to changing the autoplay, because it was only that very specific set of conditions that made me want to change it in the first place.