Using a Masonry-type template, you cannot control the order of your thumbnails 100% nor the number of images per row. The order will be close to what you choose but not exact (unless all the images are exactly the same size).
When hanging a gallery wall, you don't force the paintings into an order that you pre-determine, you hang them in the most aesthetically pleasing arrangement. Masonry does the same thing, although it keeps them in roughly the approximate order.
To control the order of artwork images, you have the following choices.
Rearrange by dragging and dropping:
Arrange Alphabetically or Most Recent First (most recently uploaded):
If you are using Collections, please see this FAQ:How do I reorder, rearrange, the images in my collections?
NOTE: If you land on this
No Opportunity to Reorder Images
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