empty gallery page

Hi, I don’t know why but since yesterday all the gallery pages are empty, I can’t see the photos even if I didn’t move them: http://www.torneidellamicizia.it/sito/foto
Yesterday I had some problem with another plugin (event registration) so I had to activate and deactivate all plugins, then I started to have this problem. But I don’t know what happened. What can I do? I have also uninstall and reinstalled nextgen (keeping the same tables) but the problem remains.
Thank you!
elena

http://wordpress.org/extend/plugins/nextgen-gallery/