For the arrows, I am not sure, but I think that the MP3 music portion, you have a copyright issue. I am sure that the DDR music MP3s are probably owned by a record label, or a music publisher. I know some of them, in fact are owned by Interchord Japan, and Toshiba EMI. In the US, I bet the rights are owned by Capitol or Virgin, because EMI owns these labels.
Sharing these would probably refer to these cases:
A&M Records et al. v Napster Inc.
Fonovisa v. Cherry Auction Inc.
In Re: Aimster Copyright Litigation
Metro Goldwin Mayer Studios et al. v. Grokster LTD.