Hello :)
I'm using this wonderful plugin to develop a website, you can see it's still a work in progress as I'm using the sample images you use in the demo :P . It was working properly before, then I started tweaking the CSS (mainly the menu below the title) and I have to say I screwed up, because it is just me coding the site, but I really don't know what I did. I already tried turning off every property included on my CSS file and it did not resolve the issue, so I would lean to say it's not on the CSS but don't know what the issue is! :( Please help.
This is the direct link to the gallery:
maximumstudiopr.com/prua/index.php/photo-gallery