OK Kim, no idea why this would work when you are logged in but I can tell you why it doesn't when not logged in ;)
Your theme has it's own fancybox backed in by way of two lines in the <head> section (probably header.php)
<script src="http://69.89.31.63/~momlove1/wp-content/themes/multidesign/js/jquery-1.4.2.min.js"></script>
<script src="http://69.89.31.63/~momlove1/wp-content/themes/multidesign/fancybox/jquery.fancybox-1.3.4.pack.js"></script>
This creates two problems. First, there is (an older version of) the jQuery library that gets loaded for the second time and then there is the FancyBox extension that gets loaded for a second time. A javascript conflict is the result.
You can solve this by either switching off my plugin or rip out these two lines from your themes header.php ... and while you are in there, move the lines
<div id="fb-root"></div>
<script>(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) {return;}
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/all.js#xfbml=1&appId=191885344226672";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));</script>
to anywhere more sensible that inside the head section... but this unrelated to the fancybox issue ;)
kfrost
