To install Syntax::Highlight::Perl on your system, as root:

perl Makefile.PL
make
make install

If you do not have root access, use the PREFIX argument (and, optionally, INSTALLMAN3DIR for the man(1) pages) to Makefile.PL:

perl Makefile.PL PREFIX=[LIBDIR]
make
make install

Syntax::Highlight::Perl::Improved is Pure Perl and has no dependencies. To install this module with only FTP access, simply create the appropriate subdirectory, Syntax/Highlight/Perl, under whatever directory you are using for Perl libraries (you will probably have to `use lib' that directory in your script) and upload the module (Improved.pm) into that directory.