Ddr Ultramix 3, Custom songs to add? Options

[Iloveanime]

Is there a way to add custom songs onto the game. I like the game but some of the songs I don't care about or just to much overplayed. Does anyone know on how to switch a song out of the game and use another? Or make the songs the right format and do the dance configuration? I figure that if you get the song you want to overlap the song you want to get rid of you could create your own foot timeing on the game. The game is in a weird format and the songs and the backgrounds are separated. Does anyone know of anyways to do it or anything? I love the game but I just want more music Thanks a lot Nick.