Hello,
I found an unbelievably minor bug that's more of a curiosity than anything else. I wanted to use my favourite memory card via snac and when booting into the bios memory card screen the memory card was not found. I was worried my memory card was defective now or worse that for some reason the snac adapter just wiped my card. I was using a different card earlier and it worked fine.
I then remembered that this card had a tonyhax save file for booting burned disks using tony hawk's pro skater 2 (documentation here https://orca.pet/tonyhax/). I actually really wanted to use tonyhax on my Mister just for a fun meta joke where I'd boot into Tony Hawk 2 and then use the save to boot into another game from Tony Hawk 2.
Anyway, after deleting the save file using my original PSX, the Mister core was able to read and write to this memory card fine.