The “Please do not leech” message occurs at line 41 of generate.php. When checking for a valid referrer, the URL “www.your-domain.com” is hardcoded into the source code on line 39. If you skip the execution of the conditional from line 40 to line 42, the PDF does get generated.
by default,the plugin try to protect your site and avoid other site link to the pdf generate page on your site.
If you visit the pdf generate page directly,you’ll get “Please do not leech” .
the plugin was designed to limit visitors to click the pdf generate link only via your own site.