The preferred method for installing the dependencies is Homebrew: http://mxcl.github.com/homebrew/
$ brew install erlang cmake ftgl json_spirit gtest
Install from MacPorts from http://www.macports.org/
$ sudo port install erlang cmake ftgl json_spirit google-test
You can also install Erlang form source as described in INSTALL.MacOSXErlangFromSource.md