Thanks Jeff, I eventually worked this out for myself. The problem I had was that my app had originally beena private app but was subsequently changed to a public app. For some reason Glide overrode the instruction to display a single value image column and continually reverted to the image for a user in the original User table. I got around this by creating a new table with just the images for the people in the scores table.
Thanks again for your speedy response.
Regards
Andrew