Nice work with this. You are really rising to the occasion by working with the constraints of the moviemaker program to make your points. A couple of technical issues--you can fade in and out on the music clips for smoother transitions. Since you have so much text, you'll want to proof it and make sure it stays on screen long enough for readers--check format of film name; also the reference to the city being united might be better as community or culture, etc.

The big thing I know your thinking about is how the ideas tie together. I think there is a missing piece at the end--the way that music brings redemption after the selling of the soul to the devil. This might be done with the walk that lonesome valley song before the flood, or it could be with the final lyrics of the blind prophet--you may have to use a bit more text before or after that piece to draw the connection with the ending point about the film as groundbreaking regarding music.