I've heard that a Mod Chip has been recently created for the GCN, that allows it to play Mini-DVDs. It might be possible for you to use that and burn the homemade software to a Mini-DVD, and base it off that. Although maybe the software has to be designed to play like that, I don't know, yet.
I know Mod Chip talk is frowned upon here, but I'm just pointing it out since it relates to playing homebrewn games.