I had response from cyberlink and they said I should have saved as packed project.
If this is the case why when you select save as you only get .pds as option ? What is that for then?
Also the autosaved is .pds.
I have not moved or renamed anything.
I think installation did not work properly as I have another pc I installed on and both autosaved and save as .pds still work with no black thumbnails. Guess I will re install on home pc.