I am working with the Catch Evolution theme- the free version. I am having an issue with image size as well, but different from the discussion above. When I create a post and resize an image within the post editor it looks fine. But when I publish it the image reverts back to the original size. By viewing the source code for the posted page I can see the new image size dimensions, but that is not what shows up on the screen. Only the full size image appears.
Another issue related to the image size is when I upload and image library the full size option is the only one that appears. I am accustomed to other themes giving an option for thumbnail and medium at the very least. Can you help me to remedy this?