Ok, I just spent the last hour debugging my plugin on your site and found it’s not my plugin that is the real cause of your issue.
It appears you have really hacked up the index.php page in the twenty eleven theme. It is no longer using the stand WP query method and so my plugin will not be able to properly determine what posts are being displayed on the home page. I am using wp_reset_query() after my loop but since you are not using the standard query loop that just causes it to loop through all the posts that would have been displayed in the standard query.
If you just want to list one post per page on the home page I would suggest going back to the standard loop in the index.php page and just changing the WP setting for Number of posts to display per page to one. I would be happy to help you more but I already spent a lot of time troubleshooting your site for using my FREE plugin. Next time you should test it on an uncorrupted theme first to see if it’s really the plugin’s fault, or at least warn the developer that you have make custom modification when you ask for help.
No hard feeling though. This is a learning opportunity for both of us.
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Aloha, Eli