I hate to be picky but I don’t want to use an image link to the m3u, as instructed in the link you provided. Although I do appreciate your help. Besides, there’s no difference between using a text link and an image link to play the m3u.
I’ve done this on my previous non-WordPress site and I had no problem. Basically creating the mp3, saving it as an m3u file in a text editor, uploading both to the server, then providing a text link to the m3u on my Web page.
I read somewhere in these forums about uploading to the server in binary? Not sure if that’s relevant.