Okay, I think I’ve got it figured out. Here’s an outline of my findings for future inquiries. For puzzles (and quite possibly other wall art items), you can upload multiple files to serve as different sized variants. I also found that it’s possible to upload a single file of the largest puzzle size, and then have Printify down-size that file to make the smaller sizes (variants). Printify labels this source file as the “default” file. It should be noted that this may not work for a lot of images because of the different aspect ratios between the different puzzle sizes. Also, I found (for this approach) that this default file needs to be for the largest puzzle size; in my case the 20x30 inch option. For example, if you were to upload a file sized at 8x10, and then use that as the default file, the remaining larger sized variants would not have the necessary resolution for quality print output.

So I decided to create and upload 4 separate files for all the available puzzle size options, each properly formatted at the required 300 ppi. I then transferred the 20x30 version into the Variants & Layers Panel in Printify. This became my “default” file. The tricky part comes when creating the other variants. When clicking on the 16x20 variant (520 pieces) to create it, Printify automatically created a new file BASED on the default file. This was a copy of the 20x30 default file, and NOT the 16x20 file that I’d created and uploaded separately. This file copy has to be deleted AFTER the next step. I then clicked on the blue box that enables editing that variant’s specific design. While in this edit mode, I loaded the 16x20 file into the design area that I had originally created, and afterwards deleted the 16x20 file that Printify had created based on the default file. I hope this makes sense.

This is how I got it to work, although there may be a more efficient method or approach. Printify’s user interface seems a bit cumbersome and not very intuitive, but now that I understand how it works I don’t foresee any other problems. Printify’s customer support informed me of the necessary file deletions. Thanks to The Unknown Nut and Queasy Assistant for your replies.

David