Thanks for your response, Sandy. Yes, I do mean the keys that exit the games.
The Start and Select buttons don’t seem to force an exit. Weirdly, my daughter found that the right-front button + front-right button does force an exit (I hope that makes sense; one button is on the front and another is on the side). So I think I’ve got the mapping done wrong there.
I think another problem is in the mapping of the shoulder buttons. I didn’t think they were required for SNES games, but I see that they do things within RetroPie.
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