no, when playing a game in mame, the mouse buttons act just like any other buttons. so, for instance if i am playing Donkey Kong, if i press either button 5 or 6, absolutely nothing happens. if I am playing Street Fighter, it will kick. when mame is running, it blocks all windows funcionality of the mouse. when i go back to the front end (MALA) if i hit button 6, it is just like right-clicking and the menu pops up.
it works beautifully