Javascript does not allow you to load XML files cross domain for security reasons.
For future reference here is the solution to load images from a different domain.
To host a gallery at: www.example.com/gallery/ and pull images from www.cdn.com/gallery/, do this:
1) Upload gallery folder to both www.example.com/gallery/ and www.cdn.com/gallery/
2) Edit embed code on www.example.com/gallery/index.html to look like this:
<!--START JUICEBOX EMBED-->
<script src="www.cdn.com/gallery/jbcore/juicebox.js"></script>
<script>
new juicebox({
containerId : 'juicebox-container',
configUrl : 'www.example.com/gallery/config.xml',
baseUrl : 'www.cdn.com/gallery/',
galleryWidth: '100%',
galleryHeight: '100%',
backgroundColor: 'rgba(255,255,255,1)'
});
</script>
<div id="juicebox-container"></div>
<!--END JUICEBOX EMBED-->This will load everything except the XML file from the CDN domain.