Because it’s BETA software, it likely contains bugs and should not be used on your live site yet; instead use a test site. If you’ve got a test site, download Print My Blog Pro here, upload it to your site, activate it, and use it to create a few projects and generated PDFs.
If you don’t have your own test site, please email firstname.lastname@example.org and I’ll give you access to mine.
Note Regarding Testing: the old free quick-print option is unchanged—that will remain as the free option. You should instead try creating a “project”, which uses the new Pro features.
Once that’s done, please let me know your throughts below.