: The "parent" game contains the core "pieces" (common data), while "clones" contain only the specific files that differ. You need both pieces to run the clone.
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If you downloaded MAMEUI (a version with a built-in graphical window), the setup is the same. Place the zips in the roms folder. You can usually change the ROM path in the settings menu if you prefer a different folder. : The "parent" game contains the core "pieces"