Perfect.
Download and unzip this file:
Import Quick Macro Core.txt.zip (9.8 KB)
It's a text file. Open it and copy the contents.
Find this action:
Replace what's in there with the new script.
Then run the Import again and post a screenshot of the error message.
We'll have to follow this workflow a few times until I can narrow down the problem.
Thanks!
Dan,
Sorry for the delay. I had to come down from the Steelers game. 
I replaced the data per your instructions. Nothing happened. No Error and no new macro creation. Let me know if you need any logs.
No problem. I'm willing to battle this with you.
KC
No worries.
Nothing happened. No Error and no new macro creation.
Dang! What a PITA. OK, time to start logging a bunch of stuff. I'll get back to you.
OK, I think I've got a handle on it. I'll post something later this evening, or tomorrow.
Bet. I’ll keep testing as long as you keep trying. Take care.
Remove your old macros, and give this a try:
Import Quick Macros.v2.1.kmmacros.zip (15.6 KB)
@DanThomas!!! You did it! The perseverance of the great Dan Thomas!
Thank you so much for your time and skill set in creating and fixing this! I am very appreciative of your efforts!
Regards,
KC
Awesome! Thanks for all your diligence. 
The fix is actually pretty silly - meaning the problem was silly to begin with. I think I wrote that code before I knew much about how the internals of KM worked. Once I said to myself "You know how to do this, you've done it a bunch of times before!" and stripped out the poorly-written code and replaced it with how I do things now, it was pretty easy.
I still expect strange things now and then, because of those quick macros that won't go away. But time will tell. Keep me posted if something goes wonky, and particularly if you ever have to do the Picker again.
I'll update the OP now.
Just wanted to report that the UUID selection did change. Thank goodness you added the Import Picker. BRILLIANT move Sir! Kudos and Thanks again!
KC
Do you think this is a new UUID, or is it one of the old ones? Because I'm thinking that I could initially filter out the ones you've already "crossed off the list", so to speak. You may not be able to tell, since I don't actually show you the UUIDs.
Let me know what you think.
Dan,
I have no idea. I've copied the UUID, of my latest Imported Quick Macro, and searched inside the Quick Macro.plist and I see nothing remotely close.
You are correct. But, I'm willing to battle if you want to test a filter theory.
KC
OK, cool.
Add the action in green:
The text is %Variable%Local_UUIDs%.
Run the picker, then you can cancel it. Paste the clipboard into a text editor, and it should look something like this, only longer
31393F5A-FB52-4BF5-A1CA-4252B04A0523__✓Quick Macro1
39CC17A4-6CEE-4837-BA3B-11FD38791A80__Quick Macro2
You can see the Quick Macro UUIDs, before the double-underscores.
So just save these somewhere, and the next time you have to run the picker, see if the new Quick Macro uses any of the old Macro UUIDs, or if it gets a new one.
I hope that makes sense.
It makes total sense. Right now the check mark is on the Quick Macro1 (there are 7 of them) whereas before I had to select Macro4 for it to work.
I'll run several tests and jot it in this text file. I'll report back to you since it took several days for this one to need a picker change.
Thank you!
Thanks so much, and no hurry. I'm only just now starting to use it again, since I got so used to it not working. So it's OK if it takes a while to get there. At least it's working now!! 
Hi Dan, thank you!
I read this thread you had to get this working. I particularly identified with your request directing the conversation to keep the communication clear.
Anyway, I used as directed and got an error. See Pic.
I did put a copy of the Quick Record Macro and your three pieces in a separate Macro Group.
Running Keyboard Maestro 11.0.3, MacOS 14.5
Additionally, I'm guessing that each running of your Import Quick Macro doesn't actual create a new seperate macro that will show up in this new Macro Group as there wouldn't need to be a picker if that were the case, yes?
Thoughts?
I have no idea why it doesn't work for you. I'm on Ventura, so maybe something's changed in the latest macOS.
I wish I could help, but since I can't reproduce it here, I'm afraid you're out of luck. I know that sucks, but there really isn't much else I can do.
(I really need to update my OS. It's just such a PITA when things break...)
Not a purely Sonoma thing -- I've just downloaded from the OP and everything's working fine in macOS 14.5 on an Intel iMac. Even moving them to a Group named "Quick Macros" didn't break anything.
Well, good thing I don't need to upgrade to Sonoma, since I just found out my 2017 iMac with the 5k Retina display can't install it.
And of course Apple doesn't make the 27" version anymore. Bastards. The last thing I need to do at 67 years old is to move to a smaller screen.
I'm digressing of course, but I'm kind of ticked right now, so I need to vent.
Luckily, my 2019 and 2020 iMacs -- both repurposed from our Admin team when we moved them to laptops when lockdown hit and WFH was introduced -- should be good even for Sequoia (minus some of the fun stuff 
).
I, too, have been holding off for a 27-inch M-series iMac. But my reserve shopping list, in case of hardware failure and expecting no new big iMac, is M2 (M4 if I can along for long enough) Minis with third-party 27-inch displays -- probably the Philips P or B Line, but there's loads of options out there.
RIP, 27-inch iMac. I've done my venting, I've also bargained with the fund-holders and been depressed by their answers. I'm now at the "acceptance and hope" stage...
Thanks for commiserating with me - it helps. It'll be a long time until I get to acceptance though. And it's so frustrating because I just want to throw money at the problem to fix it, and it's like they don't want my money. Ugh. Oh well.
