Hi,
(my english is not perfect but...)
For my part i'm always interested when someone tries to mix interactivity with a "classical" form of art.
The start of your "game" is a little rough because all the voices start at once at the same time.
Now if you ask me what I would change, I think I would try to differenciate the voices a lot more. For exemple I thought the shadow of the character on the right was a man while it has the voice of a woman. The three voices sound too much similar to me and that's a problem.
Secondly it is always interesting to have an idea of how long the clip (or whatever) is. You know like the red line in a youtube video.
Voilà. Now i hope you'll find more help from better game dev than I am (which I'm not really).
It's really sad for the "dance theatre in an art gallery" project... It would have been cool.