Okay, just some news (sorry, I losted the files somewhere but found them today), I guess you were right 'cause I've just tried it on my other computer and it works perfectly thanks for the help anyway !
But I have some question : Is there a way to limit the fps (I have a 144Hz screen in the game is playing like x2) and did someone figured out how to use a virtual card (for saving, unlocking songs... ect) ?