WARNING: GIT IS BEING RESTRUCTURED
Compiz is undergoing major changes and this guide may not work with the git sources. For the time being, please use the source tarballs (.tar.gz or .tar.bz2 files) from the compiz releases link below.
Compiz Support Team
A guide outlining how to install current master can be found here.
The following patch includes the changes I made to the Xorg XKB files adds a keyboard model for the MS Digital Media Keyboard that maps some of the multimedia keys: