I submitted an app which made by AppUp Creator, and it has been rejected today. One of the rejection reason is "Angel Fan (Facebook) tab of the application does not display anything". Actually , there has contents in this Facebook Page, but it need over 20 seconds for loading the page. I think some issues cause the page loading so slow, (1) network transfer (2) Widget too slow . Maybe you can add some message in this Widget that can tell users that this page is loading, like your RSS Widget, as below:
Para obtener más información sobre las optimizaciones del compilador, consulte el aviso sobre la optimización.