Exclude images does not save

I am an artist and I have set up my website with a nextgen gallery. What was working for me in the past was I’d make only a couple of galleries, one for new work, for the home page, and all of the paintings in one other gallery. Then I made different pages for different groups….All Paintings….Available Paintings…Available small …Available large… And how Id do it, so it would be easier, is insert the big gallery of all paintings, on each page. Then I’d go into each page and simply Exclude the images that did not fit the profile of the page, by checking the box “exclude” beside the image. It has worked fine until last year.

Now, there is no “save changes” button within the editor window, like there used to be, only “Insert Gallery” at the bottom. There is a “refresh” button, and an “x” in the top right. Non of these buttons when clicked , and then updated the page afterwords, makes any change. I still see images I have clearly checked “exclude”.

How do I save changes so that the ones I want excluded are excluded? The ones I excluded already before last year are, its just any new images I put into the main gallery now are not “excludable”.

I have a Mac, 2017, work on FireFox system Sierra.

The page I need help with: [log in to see the link]