10 credits
Hold [Select] and press [L], [R], [Down], [L], [R], [Down], [L], [R], [Right] at the options screen.
Background music selection
Hold [Select] and press [R], [L], [R], [L] at the options screen.
Expert mode
Hold [Select] and press [Up]x2, [Down]x2, [Left], [Right], [Left], [Right] at the options screen.