For regenerating the documentation you will need doc++ for generating the class documentation. Alternatively the Makefile system will try to use kdoc or scandoc (included), but might fail halfway during class documentation generation. Also, latex, latex2html, netpbm and plenty of disk space on /tmp are required for generating the online docs. However, the distribution includes a file Mdoc.tar.gz in the doc directory. As long as you leave this file there, the Makefile will not attempt to regenerate the documentation but use this instead.