IDM grabbed the file for downloading via my browser but it appears to be an mp3 file.
seems to download ok through the itch desktop app.
Oh, sorry for the misunderstanding! The file up for download is the song used for the game (I put a ♪ on the name but as I feared it is a tad hard to see). The game was meant to be played on the browser - I'm surprised the desktop app provides a download link :o