Finally I found the problem: the SuperNews Theme!
Here a picture showing how images are on my blog now (I already bought the theme 🙁 )
And here how it show the images on the early theme (atahualpa)
Seens to me that something is wrong wiht the area for posting.
If I delete a gallery and post it again, it show ok. The problem is that I can´t do this to my past posts I have almost 1k posts already published.
Some idea how to solve this?