Thank you very much for y9ur help on this problem Ray, it's much appreciated.
Just at the moment, the owner of the site is in the hospital with health problems, but I'm sure he'll enjoy his website again when he returns home.
Just a further favour would help me if possible. I have two other sites using the same power gallery and having changed them as you suggested in relation to the PHP version, one works correctly but the other isn't showing the images, What might be wrong in this case, please?