New authors not showing in list

hello,
thank you so much for this plug-in! I’m just working my way through this but I’ve noticed that the authors that I’ve added (non-users) are not showing up in my list? When I click Authors, they all show up with their names, emails and author url’s but I also notice that they show up as zero posts next to their names. I’ve updated the posts to match them as the author though, and when I click the ‘zero’ I also see their posts. So I’m a bit confused at what I’m doing wrong…
Thanks,
Allison