Thank you for playing it, and thanks for the link. That is a generous offer.
Honest answer about the game itself: I am not planning background music in it. The whole idea is a quiet puzzle with no clock, and I think music would work against that. Most players would turn it off anyway. Where music would actually help me is outside the game. I post a short clip every day on TikTok and YouTube, and there is a trailer. Right now I use library tracks, and that means I cannot use the same track on both platforms. One short piece of my own would solve that. Something that loops, twenty or thirty seconds, calm but with a pulse under it. If that still interests you, I would need it in writing that I can use it commercially: in the trailer, in the clips, and in paid ads if I run them. The game has optional in app purchases, so it is a commercial project and I do not want any grey area later. I would credit you by name with a link wherever the clips go. No rush, and no problem at all if that is not what you had in mind.