We sell magazines and have tried password protection previously with lots of negative feedback and support needs from customers.
I think a better way to protect documents with out usability issues with customers is to water mark the document so it's traceable to the purchaser.
This could be done on the cover, the table of contents or other page or by watermarking the footer of each page.
If your download plug-in allowed for this I would purchase and uses it right away.
Would this be possible to implement?
Thank you,
Alan Niven