Captivate 12 - recording shows blank slides - but visible on preview

I've tried recording a software simulation as Training, Assessment and Demo and I am getting the same problem.  Once recorded, the pages and thumbnails on the left of Captivate are all blank, its not showing the software screenshots.  It does show the Captivate added e.g. "Select button" direction but there is nothing but white space.  When I preview the project, it shows as it should.  I've tried restarting and getting the same outcome over multiple days.  I am well used to the old version of Captivate.  Any ideas why its behaving like this and how to resolve? Its not actually usable right now.

Screenshot below of my recording and one underneath is when its previewed ....