I had the same problem after updating to Nextgen 2.1.2 and WP 4.2.3.
Setting Galleries to “not linked” worked for me. (one by one, ugh… couldn’t this be a bulk actions option?)
Worked for you too, apparently – went to your page and the gallery links open normally – the top of the page above the galleries has 2 lines reading “no images were found”, but I see galleries below and they open. Are you aware of this? I was having the problem seemingly persist until flash/refreshing the page, fwiw.
