I have a featured image on http://friends-of-lewes.org.uk/tree-surveys/ which I also wanted to use on http://friends-of-lewes.org.uk/current-concerns/friends-of-lewes-projects/lewes-urban-arboretum-project/
It is 1977x498 pixels, and I am using Coraline.
I followed the instructions on your help page (full size, use as featured image, update) but the featured image refuses to appear. Why is this?
Blog url: http://friendsoflewes.wordpress.com/