I use the archive.php template for author information display.
The page displays the number of posts of the author with the get_the_author_posts(); function.
With Co-Authors Plus enabled, I have some authors for which the display is 0 despite the fact they have published posts. I had a look to ng_term_taxonomy content and saw that the "count" value was set to 0 for each author who was not involved in a co-authoring post.
When adding one of them to a post, I saw that the "count" value was properly updated, and once remove as co-author the value was still correct.
Did I miss something to do after enabling the plugin in order to have the "count" value initialized for each author avoiding this issue ?