I'm using InDesign CS5.5 withthe latest update along with the latest Folio Builder tools v20. When trying to preview articles using File>Folio Preview the Folio Preview panel opens and is blank. Using Overlay Creator's preview I have Adobe content viewer opening and there is a preview. Is this a bug or am I missing something. Never had this problem before.
Previewing from that menu runs "preflight" tests that run and block content that would break content in the viewer, since that view is of a whole folio and not a single article. To make sure you see your article, make sure you have resolution and orientation matching the definition in the folio. The most common mistake that yields your issue is when a user sets their folio as dual orientation but has an article with only one orientation set.
Please follow up if you are sure your folio is in good shape, but your preview still does not appear. Thanks.