The bootstrap fails on Mac OS X. The launcher hints to this issue:
http://stackoverflow.com/questions/14806709/application-is-using-java-6-from-apple-instead-of-java-7-from-oracle-on-mac-os-x

The bootstrap launcher shows:
System.getProperty('os.name') == 'Mac OS X'
System.getProperty('os.version') == '10.8.4'
System.getProperty('os.arch') == 'x86_64'
System.getProperty('java.version') == '1.6.0_45'
System.getProperty('java.vendor') == 'Apple Inc.'
System.getProperty('sun.arch.data.model') == '64'

The current version is 1.7.25 and my java_home is set correctly.

Please rebuild the dmg with the suggestion made from the stackoverflow answer.