Gallery Help

On the website, https://nickeldesigninc.com/our_work-2/, we are having some gallery issues. The concerns are:

1. Just upgraded to WordPress 4.2.2, now there are green bars under each image. Some have no copy, some say “undefined”. How do I remove this?
2. When you hover over an image, it highlights in a green square. Is there a way to change the shape of the square to a circle?
3. When the page loads, each image has a dark green square in place, while loading. Can the dark green square be removed or changed to white?

Thank you for any help