File/include folder .. The required folder for the photos was shown there but there was no option in the main screen to select other than one folder with just four photos. The folder location was shown horizontally at the top of the screen and clicking on it offered no further options.
Have sorted it now, but not sure how.
The main screen now displays running vertically on the left of the screen, a hierarchy column of folders to select from. - Previously there was no option to select an alternative source.