IMG Numbers in Photos

Photos cannot sort the photos by the filenames, but it can sort the photos by the titles. If you copy the filenames to the title field, you use this to sort your photos by the numbers you are seeing in the filenames.

You can run a script to copy the filenames to the title filed, see this script, for example:

Script: Batch Changing the Titles to the Filenames with Extension (Dec 19,2018)

The difference between Automator and Script Editor is, that Automator is a tool to combine actions into a workflow. It can include actions, that perform Apple Script code. I am not sure, why the Automator workflow is not working for you, since I cannot test this on my system.

Script Editor is an application to run Apple Scripts directly from the editor, the naked script without bells and whistles. It is easier to debug, because we can see the the error messages.

I am glad, you could get it to work.

To see the titles below the thumbnails open the "View" menu in Photos. Then click the menu item "Metadata" and enable "Titles".

I can no longer test in High Sierra, as my Mac is now running a newer system. How many photos have you selected, when you ran the script? It may have been timeout errors, when too many photos have been selected.

I'll try to add a different version of the script with more error checks.

Run it directly from the Script Editor.app. Paste the script into the editor, then select a few photos in Photos, then run press the "Run" button in Script Editor:

-- batch change the title of images to the filename
(* How to use this script:

Open this script in Script Editor. Launch Photos.

Select photos while viewing the  "All Photos" album; this works better than Moments or smart albums

When all all photo are selected press the "Run" button in Scripteditor. 
*)

set imageSel to {}

tell application "Photos"
	activate
	-- process the selected photos from the All Photos album
	try
		set imageSel to (get selection)
	on error errTexttwo number errNumtwo
		display dialog "Cannot get the selection: " & errNumtwo & return & errTexttwo
	end try
	
	--	check, if the album or the selected photos do contain images
	if imageSel is {} then
		error "Please select some images."
	else
		repeat with im in imageSel
			try
				tell im
					set its name to its filename
				end tell
			on error errText number errNum
				display dialog "Error: " & errNum & return & errText & "Trying again"
				try
					delay 2
					tell im
						set its name to its filename
					end tell
				on error errTexttwo number errNumtwo
					display dialog "Skipping image due to repeated error: " & errNumtwo & return & errTexttwo
				end try
			end try
		end repeat
	end if
end tell
-- display dialog "Done"
return "Done"

Which system version is running on your Mac, Doug?

You're welcome Doug. 😊. You are living in a very beautiful country. I have very fond memories of hiking the Milford Track a long time ago!