I am getting the exact same error. I am however able to save state up to 10 or so SNES games before I receive the error. I have 46 SNES games split in 2 folders. And even though they are in different folders. I am still unable to get more than 10 save states for SNES games. I have tested this extensively but I do not know how to remedy this. I also have 650 or so NES games but they work flawlessly.
Thank you for verifying that I am not crazy lol. I think it had something to do with the .hmod file. I had tried to install/uninstall a couple of them and it may have messed something up. That and the number of files being shown.
I have since went back to a fresh install of hakchi2 2.12 and using Cluster's original .hmod for retroarch. Then I reduced the number of roms to my favorite 300 NES, 30-40 SNES and 25 or so Sega Genesis. There are only 30 per folder, automatically separated, evenly by first letter.
Side Note: messing around in RetroArch Audio settings(turned on audio syncing I believe), I was able to make music/sounds on SMW2 Yoshi's Island MUCH better. I can't wait to get back into that game! Hope this wasn't a fluke and helps others!
Thanks again everybody who has poured their blood, sweat and tears into this wonderful program! Cheers