I just got my pie and Retropie set up today. The ROMs are all the right types. I’ve put all my emulators in the correct folders according to the wiki, but the only ones to pop up are my GBA games(which is giving me a missing bios message as well). Any way to get Retropie to recognize everything?
If unzipping them didn’t work it could also be a poor source of ROMs or you could verify your es_systems.cfg file was set up properly by typing sudo nano /etc/emulationstation/es_systems.cfg each system should match the file types listed on the wiki pages.