I really like this film...
Never heard that music before at the begining..... I would be interested in seeing this though if you ever get around to finishing it off or doing something with it.
Top tip = if you added that music it does not work try to stick with the OST or re-use another track of the OST if you can find it
came across this the other day and might work in this film
Earth Floor by Michael Brook and Brian Eno
http://www.youtube.com/watch?v=35jRNluLBTo
Michael Brook - Skip Wave