You can download the CSA sources from this link. Read files README and INSTALL, that accompany the CSA source distribution. Most important, to run CSA you will need to have all of the prerequisite software utilities listed in the INSTALL file. As already outlined, CSA works with UNIX, not in addition to it, in that it relies mostly on underlying shell commands and utilities. By default, CSA is installed in /usr/local/csa/, but a different installation PATH can be specified at installation time. Again, see the relevant INSTALL file. For the rest of this document I will assume that you installed CSA in the default location, /usr/local/csa/.
CSA is designed to be run under a non-privileged user. If your Web server runs with root privileges even when it calls CGI programs (a sure way to fishing for troubles), I recommend you install a proper setuid wrapper. The one that I normally use is cgiwrap which should work with any Web server that provides a standard CGI interface. Alternatively, if you run the Apache Web Server you may want to configure Apache's own suEXEC CGI wrapper. In the examples that follow I will assume that cgiwrap is used, but the explanations can be adapted to suEXEC with only minor changes. I personally use both Apache and the Boa Web Server, so I tend to prefer approaches that fit both of them. I will therefore assume that a user's CGI directory be $HOME/cgi-bin/, and that user's HTML documents are located in $HOME/public_html/. Installing and configuring the setuid wrapper, or any other prerequisite software packages and utilities is outside the scope of this document, and will not be covered here.