It's finished. A new PPA is available for Comtpon, the lightweight compositing manager. Thanks to cchj and Richard Grenville we have a new thirdparty repository available. It has been tested on both Quantal and Raring, and I must say it's pretty stable. Just follow the instructions provided at the Compton page at Tips'n'Tricks. Enjoy!
PS. Soon I'll update the configuration guide to modify the settings file without using pasameters at the command line.