That's certainly an odd issue. I haven't seen that happen before. I'm not certain what's causing it, but here's a couple of things for you to try:
- Remove the
"_id": "57e0683ebfc7a6d0523235b2", line from the HTML embed
- Change your gallery group names to have no spaces. EG
Fully Staged Homes becomes
Fully-Staged-Homes - I don't know if that makes a difference or not, but it could possibly read spaces as multiple groups.
- You can also remove the
"cdnUrl": line, I've found it works without this one.
The only lines within the script that you should need are
url. You can see that in action on my example page which has the latest version of this setup on it.
Try those and let me know how you go.
Also as a note, if you want all three of those galleries to show up in the same lightbox, they all need to have the same group name. If on a page you want several galleries to all display together, just manually set the group to something like "gallery" rather than using a dynamic field. Using a dynamic field for the group name is only if you want multiple lightbox galleries on the same page but don't want them to show up together in the lightbox popup (like on my example page).