Tony & Team: thanks very much for your fabulous work! I had some challenges getting things up and running from 10.7.4 Lion, but I worked through those the old-fashioned way; I read comments, forum posts, and ultimately a combination of the efforts of others resulted in success.
UniBeast 1.5.0 did not make my USB flash properly. Worked around this by using UB1.4.0 after copying the ML app to /Applications.
Only managed to get ML to install by using PCIRootUID=0. After that could not boot at all without -x safe mode, but once that was done using MB4.6.1 to install EasyBeast, SysUtils, and Unified Audio Injector with HDARollback I ended up with a fully-functional system.
Thanks everyone, keep up the great community work.