ive tried several stage expansion packs and codes, and when i press on the stage it freezes without the loud beeeeeep. Im using riivolution and an XML that lets you put every brawl hack in 1 folder, if that matters.
If you're using riivo then you will have to use riivo's create function to add the extra stages in game. Codes alone won't work in riivo to create files (after what I know)