Bom pra colocar no menu, select e no versus,vão até essa linha aki do system.def, na pasta data mugen do seu jogo...

[Music]
;Put a filename for a MOD, MP3 or MIDI here, or just leave it
;blank if you do not want music. If an invalid filename is
;given, then no music will play. To play CD audio, put
;the track number followed by ".da". For example, to play
;track 3 from a music CD at the title screen, use:
; title.bgm = 3.da
;To play mymusic.mp3 from the sound/ directory, put:
; title.bgm = sound/mymusic.mp3
;Music will continue to play between screens if the files names
;are the same, and both BGMs are specified to loop.
;Music to play at title screen.
title.bgm = ; MUSICA DO MENU AKI
title.bgm.loop = 1 ;Set to 0 to prevent looping
;Music to play at char select screen.
select.bgm = MUSICA DO SELECT AKI
select.bgm.loop = 0
;Music to play at versus screen.
vs.bgm = MUSICA VERSUS AKI
vs.bgm.loop = 1

Vai ficar assim !!!

MENU
title.bgm = sound/meuson.mid

SELECT
select.bgm = sound/sonmeu.mp3

VERSUS
vs.bgm = sound/dbz.mod

Sempre assim pessoal, não se esquecendo de colocar as referencias, .mid, .mp3, .mod, se não não ira funcionar blz !!!

Creditos ROCKLEE

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