Dear Digital Guru,
Your advise re size of file is 100% correct. I compared the photos I used previously to the current ones.
The older ones were around 1meg and below the newer ones were approaching 2megs. I resized them as you suggested and Bingo it all worked.
Incidently I had upgraded my camera from a Sony a55 to a77 which is a 24 meg pixcel camera hence the bigger files.
I do not recall Roxio ever putting out a limit on file size and that's why I was trapped I suppose.
Thanks again Problem Solved!