You can clone with
HTTPS or Subversion.
The BackTrack LiveCD environment defaults to the user always being UID 0, according to JonValt. This presents some problems for RVM.
this document with some minor changes (lot of commands could be executed by normal user) cover pretty much what is necessary http://www.darkoperator.com/installing-metasploit-in-ubunt/
Going to track this as part of http://dev.metasploit.com/redmine/issues/7475