What a dishonest plugin.
First, it does not allow you to save your options till you click on a link to allow the author to collect data about your usage of the plugin.

Second, ALL of the styles to show the related posts are PRO, except for a very silly minimalist one. You would be so shocked to see the plugins AD for PRO (paid, $$$) on your website in your posts!!

Third, it is LAME. It inserted one single link to one single completely and utterly unrelated post!