I recently tried to download several recently updated files in my digital content and got similar messages each time. They start with "This XML file does not appear to have any style information associated with it. The document tree is shown below." Under a line are a couple occurrences of "Access denied". Alternatively, I sometimes get a picture of the Golem with the error message "The requested URL was not found on this server, or you do not have permission to access this area."
I saw this problem with the Pathfinder Playtest Bundle (but not with the rulebook alone, which downloads fine), both volumes of the Book of Many Things (which previously had the super small file size problem), various Starlog PDFs from Everyman Gaming that were last updated on July 4th (and which I successfully downloaded earlier this week), and Starfinder Society modules before the recently released 1-20 (but SFS 1-20 and 1-21 download just fine, as do the three PFS Playtest modules). Basically, when I attempt to download a random file from my digital content, there is a less than even chance that I can do so. The problem is even more common with files that I recently downloaded or tried to download.
In case it matters, I am using Google Chrome as my browser.