Could this be down to me changing the sub category image size? This is the only change i've made, I've put it back but images are still not showing correctly.

The other hiccup (which didn't happen in 1.38) is that the large image defaults to showing the small thumbnail, if you pick up a small & medium image but not a large image. I can work round this, but would like the medium images to look clean on the site and not "jaggy".

Stuck.....