You cannot simply download a single "Mario Bros." file and expect it to work on every version of MAME. MAME is constantly updated. As the developers improve the accuracy of their emulation, the requirements for the game files change.
Assuming you have legally acquired the files, here is the step-by-step setup guide: mame-plus--6000-roms
The golden age of arcade gaming—a time of neon-lit cabinets, the clatter of joysticks, and the quest for the high score—never truly ended; it simply migrated to the PC. For purists and retro enthusiasts, no name carries more weight than . Among its many variants, one build stands out for its user-friendly interface and legacy support: MAME Plus . You cannot simply download a single "Mario Bros
And that, perhaps, is the real story. It was the closest thing our generation had to a magic cabinet—open it, and any arcade game ever made might be inside. Assuming you have legally acquired the files, here
Launch MAME Plus, go to Options > Default Game Options .