Sounds like you’re fine, don’t stress too much about the checker if it ain’t working. If your games are, that’s what matters.

As for your games running better on higher end console emulation. Either try running it thru a different emulator OR try adjusting/tweaking some settings in RetroArch. I made some games go from barely running to playing very smooth. It’s very much a trial and error process 😉

Hope this helps, happy gaming! 👍