Doesn’t seem like a Nitro issue to me, but the dysfunctionality of Apple Photos which only allow sorting via “Oldest / Newest” or Title. Unless you have titled the files, you’re stuck with your current issue. I want to sort by Filename, which I use “Finder Rename” to something meaningful before I do anything else. I had to buy Photos Workbench (Houdah Software – $29) which allows me to copy filename to Title, so I can THEN sort by title. This works for me, but annoying to buy another app to get it to work. I also use Finder Tags (Apples own system feature) when renaming files, but Apple Photos does not recognize Apple’s own finder Tags either (go figure!).
I would not use Apple Photos except for the convenience of iCloud on multiple devices. I use other software to manage a catalog of original (mostly RAW) files and do almost all my editing in other apps, then export to HEIC or JXL to finally import into Apple Photos.
Nitro can handle the edit / conversion to HEIC and export into Photos, but so far, the xmp sidecars are not useable in any other apps, which means that any work done in Nitro is hostage to only Nitro and things like ratings etc aren’t seen by other software… so that breaks its functionality for me….good luck…gary