The graphics are not any edit, or even close to Zelda graphics. Legally a claim of copyright infringement from those tiles alone would not hold up in any court. It doesn't matter if it "looks sort of like Zelda!" That's not how copyright infringement works. There are games out there that are blatant copies of Zelda(like 3D Dot Heroes, which is quite popular and on the PS3) and Nintendo can't do a thing about it.