Probably I have found the problem.
When I surf on the gallery page I linked before, in Chrome’s console I can read 2 errors:
1. envira-min.js?ver=1.5.3:10 Uncaught TypeError: Cannot read property ‘msie’ of undefined
2. (index):258 Uncaught TypeError: $(…).envirabox is not a function
It seems that the error number 2 is related to the Envira Lightbox.
I hope that this can help to someone that knows how to solve this problem, since I don’t think that I would be able to solve by myself…
Thank you in advance!
Yari