Hi!
As far as I can see there’s no possibility to do this, but I wanted to send this ticket as a suggestion: it would be great if we were able to move every image around when we create a masonry grid gallery. I mean, when resizing every image in the collage sometimes you want to move the image inside the frame so you can show the part of the picture that you want to be shown (since it’s resized because of the masonry gallery). It would be a good feature to have.
Thanks and keep up the good work!