The is a specialized collection of arcade game files designed for the MAME 2003-plus emulator core . This set is highly optimized for low-powered devices like the Raspberry Pi and handheld consoles. What is a "Full Non-merged" Romset?
If you are using a Split set rather than Non-Merged , you are missing the parent ROM. Mame 2003-plus Reference Full Non-merged Romsets Download
The Libretro forums and Reddit communities like r/retropie or r/roms often maintain threads pointing to the latest version of the set. The is a specialized collection of arcade game