Hi,
that looks more like a (empty?) text-line was added in the html file before the pano div element...
and due the height=100% of the pano div element everything is moved down by that line...
Maybe the FB app is injecting some code that is causing that...?
Maybe try this as fix - use an absolute position for the pano div element:
<div id="krpanoDIV" style="position:absolute;top:0;width:100%;height:100%;">
Best regards,
Klaus