I'm using mode_message and:
use constant PAGE_GENERATION => 'paged';
on my board and I see that kareha is indeed generating cached thread pages (1.html, 2.html, etc) but it doesn't create a page list on any of them. Basically the only way to get at threads that fell off the front page is to view the All Threads page and pick one from there.
Did I miss an option to have it stick a page list somewhere?