Hi,
Thank you for the reply. I'm familiar with this special env. Did you mean the following? (added a newline):

PERL5LIB=<path-to-your-local-directory>
perl -MDevel::Cover=-silent,1,-db,${cover_db}" <script>
[download]

Also, the Devel::Cover already installed in the lib of the "perl". I think it will still take the one already installed and not the one I cloned.