After running into space issues I decided to completely reinstall RetroPie to a SD card, and then go through the steps to run ROMs directly from the USB.
This meant I followed the following steps in the installation guide:
- Burn RetroPie 4.1 IMG using ApplePi-Baker.
- Setup a controller (iBuffalo SNES gamepad).
- Configure WiFi.
At this point I followed the automatic mount steps in the Running ROMs from a USB drive wiki entry:
- Update the Raspberry Pi setup scripts.
- Enable the USB ROM transfer service.
- Create a retropie-mount directory in the root of the USB (it was already formatted).
- Plug in the USB.
After a few minutes I shut down the Pi, pulled the USB drive, and plugged it into a computer. The following directories were created:
I transferred over two directories containing roms and when I started the Pi back up, after inserting the USB drive, I found that only the two emulators were displaying as an option; I no longer had the standard RetroPie item.
If I pull the USB drive out and start the Pi I see the RetroPie menu only, while if I move the roms out and plug in the USB I get kicked back to the command line after I'm told EmulationStation can't find any systems.
At this point I'm not sure how to proceed to get the missing items back, or if this is the expected behavior.