Turns out the answer was to check the box in settings to "Enable Enhanced Experience Composer".  I think we are OK now.

I think this may be related to some appended URL parameters.  With some URLs I am seeing a parameter like ?_AT_Admin=1&mboxDisable=1 being appended to the URL and our setup redirects all mixedcase parameters to lowercase, which I think is sending the preview pane into a never ending loop.  Any optio...

When selecting the URL for an Activity, certain chosen URLs will cause the preview pane to refresh constantly.  Other URLs on the same domain work as expected.  This happens with javascript disabled as well.  Is this a known bug?