Replacement Sky Question

With huge respect to @Aleke and everyone on the Photoshop Development Team, I can't help think you are making it more complicated than it needs to be, or even should be.  It seems likely that these are additional image files that exist in a folder somewhere, and that you have collected over a period of time.  So I absolutely prefer to keep them in a folder that I control, and can add to or maybe even remove from.

If that is the case, then click on the + which will open Finder.  Locate and select the folder your sky images are in, and job done.  Better still create a new Group, and _then_ locate your Skies folder with Finder.  It's a while since I created my New Zealand Skies group, but I think I was able to add new JPGs top the group and have them available.  What makes this approach even better is that the same resouce will be available for Release and Beta versions, and easily added to Majer Version updates going forward.

This is a no brainer for me, and I do it with all presets (like brush .abr files).  I keep them in a My Docs folder, and place a shortcut to that folder in the relevant preset folder.  When I add a new brush group etc. it is straight away available in Release, beta and V22.2.  The only downside is if I create new presets inside Photoshop, and I have to remember to copy/move them to my central My Docs folder.  It works flawlessly. It is safer, judging by the number of 'Where have you hidden my presets?' posts we see on this forum. And it gives you a smug feeling of getting one up on the system. 

Hi @KickingupDust! Can you try exporting your skies as .sky files and then moving those files to your new computer?
Hope this helps!
Alek