When I initially set up my WordPress.com blog, I uploaded an image which was automatically resized to create 3 different images which you refer to as a 'blavatar'. I've used this same image as the image in my sidebar to be shown via the image widget. It's one of these which causes that image to be shown as the side image in the facebook post preview that occurs when I paste the blog's URL into a facebook status message, in my news feed.
The problem I have is that the WordPress.com facebook app which automatically posts my blog posts doesn't use this image, but rather uses its own image, which has nothing to do with my blog. This is not acceptable.
You need to rewrite your app so that it uses the blavatar for the blog posts' side image on the post preview in the facebook news feed.
The blog I need help with is sunspotsoftware.wordpress.com.