As stated above, when you go to a project page (which contains a thumbnail gallery) for the first time. Everything works great. But, if you refresh the page or browse away from the page and back. It no longer works / disappears.
It’s like nggallery snapchat without a timer.
I have tested the site in Firefox and Chrome with the same results. It doesn’t correct itself if I clear my cache.
Is this a caching issue with nggallery / wordpress?