@erin @ WSK: I've checked out your site and it seems that the plugin now works fine. You might want to try to delete some of the
<p style="text-align: center;">
elements that are placed around the images to force them to be centered and those images should still be centered (thanks to the latest update).
On a side note:
Load your site and check out Firebug's console - there are a few requests to http://cdn.naturallyella.com/wp-content/plugins/.. that return 403 Forbidden error. That was the case with my plugin yesterday (and 2 days ago), but today it seems that those requests (to my plugin's files) are fixed. Maybe there's a bug with the CDN setup. Hopefully the plugin now works just as you wanted.