I haven't done this but I have found an easier way.
Install DownThemAll! for Firefox (https://addons.mozilla.org/en-US/firefo ... wnthemall/
Login to the subscribers area.
to see all available PDFs.
Configure the DownloadThemAll! add-on preferences so it doesn't too aggressively download from the server.
Right click and select "DownThemAll!..."
Wait while all the links are processed.
When the "DownThemAll! - Make Your Selection" window appears select "Links". In the top left.
In the same window select the check box "Documents (pdf, odf, ...)". Middle bottom.
In the same window click "Start!"
Patiently wait while they download.
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