Post-indexer not indexing new posts

Hi- I have installed post-indexer v2.1 onto a multisite 3.2.1 setup, following the simple instructions. I can verify that the 2 new database tables have been created after the plugin was network activated.

The problem is: new posts are not adding anything to the new tables. My setup is not using any other plugin that feeds of the post-indexer, so I have been testing by looking at the database through phpMyAdmin. When I add a new post, the wp_site_posts and wp_term_counts tables remain empty.

FYI- This setup has no regular Posts, just 3 custom post types made with Custompress.