Images and captions in posts

I think i’ve found a bug concerning the behaviour of the theme with main wordpress gallery captions.

Here’s what i do:
1_ upload photos to the media manager in wordpress
2_ “create gallery” button
3_ select the photos
4_ “create new gallery” button
5_ add a caption to every image – insert to: file media – dimension: miniature
6_ “insert gallery” button
7_ update post button

The images are displayed correctely in the right position, but the captions are displayed at the top of the page.

Try to have a look here – http://www.gr-design.it/2015/07/09/cucine-in-rovere/