I’m using PiSNES with mario kart and it works great, that sounds like a very odd bug.
If you’ve installed with the image then it shouldn’t be a problem.
I downloaded PiSNES binary from the pisnes google code website, then I deleted the pisnes folder under /emulators/, created a new folder named pisnes and then extracted the archive into that. Not had any problems although some Roms are just not supported at all, mario kart works a treat.
Good luck!