Zero post counts

After I activated and began using this plugin, I noticed that many of the 270 authors on my site had 0 post counts. These are authors who all have at least one post — some have multiple posts — and none of them are co-authors. But this began happening immediately after I installed the plugin, and I haven’t made other changes, so think the plugin must somehow be the culprit.

I can “fix” it by editing and saving each affected authors’ posts again. (In the post editing screen, and on the published page, they’re still shown as the author.) But then the next day I will find that other authors are affected. It’s never-ending.

Any suggestions? The plugin works well for me, otherwise, but I’m going to have to deactivate it if I can’t sort this out, fast.

Thanks for your help!