This is an issue I've had for the entire period of CPG usage, after this feature became available:
I have activated the rewrite rule capability, to have more friendly links. It works fine all around the gallery, with the exception of a couple of things. When I click the "Last uploads", "Last comments" or "Most viewed" links, where the links to page 2,3 and so on seems to not work;
The requested URL /thumbnails-lastup-0-page-2.html was not found on this server.
The requested URL /thumbnails-lastcom-0-page-2.html was not found on this server.
The requested URL /thumbnails-topn-0-page-2.html was not found on this server.
This is frustrating, since it basically means I can't access the pages at all.
disable the SEF plugin if it doesn't work properly with your server setup
That's not solving it, just evading it :/
mod_rewrite does work fine in any other aspect; The rest of the gallery is okay, and the main site that also uses it works.
That's why the sef_url plugin is considered and clearly marked as being "experimental". If it doesn't work for you, turn it off. That's all we can say.