Featured Page Widgets not aligning

On my home page (in development IP address only) there are four widgets that are aligning with three on top flush right and one on the next row flush left in the top sidebar just below the featured image slider. I've tried adjusting in the overriding CSS editor but nothing works. Images are 340px x 211px. Also, the media in my media library are coming in with broken links when I upload. I have installed Media Library + recently. Can you help? I'm using Mustang Premium.