Just took a look. The problem actually looks to be a conflict from another extension that's trying to apply a style to any Facebook widget.
The problematic style is in plugins/content/jaggysharebuttons/css/standard.css
.fb_iframe_widget {
position: absolute !important;
}
Can you remove or comment out that style and see if that gets you going. Leave the width at 100% in the comment settings, and I think you should be good.
Please let us know how that goes or if you need any further assistance!
Thanks,
Alex