The installation instruction from the home page is to compile everything in the tarball unpack directory (which is ./live). After compilation the instruction states that the entire live directory be moved to /usr/local/lib/ or /usr/local/ .
What I'm trying to achieve is to get homebrew to just take whatever it finds in the working tmp directory after compilation and stuff that into its cellar, then symlink the entire cellar to the prescribed location (/usr/local/lib/live).

prefix.install was the only way I found to get everything into the formula's cellar directory, but if you have a suggestion for a better tactic I'd be glad to hear it.