That is what I suspected. Version 6.1 was only available for subscription users and I suppose you had a boxed license of eLS6.
Beware: I'm not sure that this is the cause of your problem at all. Not sure if this proposal could help you: try to insert a HD Video demo slide (Insert, Recording slide, choose Video Demo) in which you perform the actions that now result in a black screen, you'll create sort of a movie slide.
Lilybiri