If after switching from another theme to ATA 3.7.3 and you see that your images don't show up like you planned.
You will have to go into the visual editor of WP, NOT HTML, and move the image ever so slightly.
This activates the DB in the CSS to recognize there's an image there. In HTML mode altering the image size does not work...it has to be done using the wysiwyg editor.
It's a bug that I am not qualified to work out.
If anyone knows a better work around I'd love to hear about it.
I have 500 posts to work through.