Gallery Shortcode with Custom theme

I posted this yesterday and am not sure why it’s no longer visible. I don’t see it in the threads I’ve started so I guess something went awry? I believe my thread does match the criteria of the forum. If it doesn’t, please let me know.

I’d like to get the gallery short code working with the Gallery Carousel Without JetPack plugin for a custom theme. The gallery thumbnails do load on the page, but when a photo is selected it goes to a new page instead of a full-screen photo with slide function. Everything works fine, in the Twenty-Eleven theme so this lead me to believe I am missing some code in the functions file or elsewhere for the custom theme, but I just can’t seem to figure it out.

Any ideas?