I have the same problem. Masonry does not work like it is supposed to, Images start in a new row instead of seamlessly flowing.
I set layout "masonry - default", but regardless of image order, there are always large spaces between images.
Even if I use the sample images from
ordasvit.com/os-responsive-image-gallery/index.php it does not work correctly.
EDIT: It works now! Maybe some older code was cached in the browser?
After a hard refresh it works as expected.