I was excited to see tome4 packaged for Guix since that game is *incredible*. However, I'm not totally sure about the music, but as for the tiles, there's this message in tome4's COPYING-MEDIA which says:
All the medias located in all the "/data/gfx" folders are granted to use with the Tales of Maj'Eyal game only. Please contact dark...@te4.org for more informations. It seems to me that we will have to strip these out. It's a shame, because it's a really beautiful tileset which adds a lot of atmosphere. I think the game is still playable in ascii mode, though I haven't tried doing it. Sorry to be a downer...