You can edit these handlers or add your own to the file. You can put whatever you want in this file. The version that comes with the sources looks for a user init file and loads it if it can find it. If you are running CM on Linux or Windows you can create shell scripts to start Common Music. The easiest way to work with CM is as a subprocess under Emacs.
CM depends on several shared libraries.
The first three are shipped with your MCL distribution. The pmcl libraries are shipped with MCL 4.2. MCL rebinds its CCL logical host to the application directory when CM boots up. This means that the MCL's help facility and other Lisp extensions won't be able to load because the CCL host points to CM's application directory instead of MCL's directory. You can reset the CCL host by adding the following form to your cminit.lisp file.