Autofocus – images on homepage

Hello

Can anyone help me with the autofocus theme? I have searched the forums and found this to be a problem, but don’t understand how to fix it.

Please see site – https://www.vickiclarkephotography.com

The images in the main homepage block are tiled. How do I get rid of this.
I have the ajax thumbnail rebuilder but thats not helped.

Then also inside each post, the photos are coming out really small no matter what I do. How can I make them larger and get them to stay larger. Is there a problem with this theme and its images? will I always have to fiddle with each individual post?

Hope someone may be able to help
Regards
Vicki