Products Categories Pages are 404

This is relation to Marketpress on this site, not WPMU Dev Dashboard but Marketpress didn't show up its the list.

We have several categories for products in Marketpress. I've updated to the most recent version. If I go to any of the category listing pages, I get a 404 error. For instance, . I tried it directly from the category setting page (for instance and it says page not found (see enclosed screenshots)
This all used to work but no longer does. Any help appreciated.