The ABC is ok.
With the exclamation mark it forces ABC to print a new line. The music then comes out to represent each line of the song. (not the normal way I know). This is the best Roger Bryant, the author,could manage when someone took it down for him. He doesn't read a note but writes and sings some cracking songs. Most of them just vanish as he sings them for a while and moves on, don't even think he writes them down half the time. KJ