First in the list is the filename (or internal name) for the cartridge (prefixed with a 'A' character), followed by lower rom and then upper roms 0-31 (WinAPE) or 0-255 (ACE).
Internal WinAPE lists internal ROMs are listed by their internal name (the name listed in the drop down when you configure the roms, e.g. OS464) .ACE always put the actual file name, even for internal ROMs (e.g. OS464System/Firmware_v3.rom). After the list of the upper ROMs, ACE also put the names of the internal Basic and AMSDOS ROMs.Then, the presence of the "CartridgeKeepExtROM" let ACE know if the cartridge ROMs should disable installed external upper ROMs or not (depending on user preferences).
NOTE: The selected Multiface ROM is not saved in the snapshot.