Versions of CGI.pm later than 3.11, http://search.cpan.org/~lds/CGI.pm-3.11/ which was released 3 Aug 2005, causes lots of problems https://lists.webarch.co.uk/pipermail/mkdoc-dev/2006-April/000323.html with the way web addresses are constructed in MKDoc.
Until MKDoc is fixed to work with later versions of CGI.pm it is necessary to use 3.11 or older.
It is easy to manually install this version:
wget http://search.cpan.org/CPAN/authors/id/L/LD/LDS/CGI.pm-3.11.tar.gz tar -zxvf CGI.pm-3.11.tar.gz cd CGI.pm-3.11 perl Makefile.pm make make test sudo make install