I’m just checking, because this has been missed by many. Did you reboot the glowforge after calibration? Are you testing each spot independently? Meaning, are you placing the test file in the upper left, using set focus, running that test and then seeing the accuracy? If you are placing a test files at all corners and then only using set focus in one spot, your results will only really be representative of that one spot where you used the set focus and not of the other spots you tested in that same run.
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Ok…I’ve done that.
I don’t remember if it is in the instruction or if I saw Dan post it in this thread (read pretty much the whole thing late last night), but it is not recommended to do more of the target test files than one at a time.
I don’t think replacing the lid cable would change your calibration. Your results look pretty nice!
i don’t think that’s what he was saying. i think he was saying that you should do the target five times, and that each time you do the target, you should use the focus tool where you are printing the target before scoring it.
Yes, this is exactly what I was trying to say, sorry it was not clear @bruceaulrich
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Ok, good to know I’m in the range. The top left one was the one worrying me a bit. It seems a little more out than right after I did the calibration, but I didn’t have a chance to do much playing with it after calibration before the lid cable failed.
I see, I just took that to mean run 5 separate times.
It’s not you, it’s me. 
You both were saying the same thing.
Measure at location, print, check
Measure at location, print, check
Measure at location, print, check
Measure at location, print, check
Measure at location, print, check
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Yes. I rebooted after calibration, used set focus on each test target and did each test individually. Thanks.
For what it’s worth, my piece was super flat, and I did 7 targets in one go, using set focus on the center… they all came out pretty damned close to perfect, with the top right corner being about 1mm off. I can live with 1mm.
Since my earlier SOS post (Sorry for all the drama!) a good reboot of all the equipment (PC and Forge), my last little experiment yesterday was spot on. I still want ‘snap marks’ so I can create re-usable jigs and not worry about skew and rotaton, but, I must say I’m quite pleased with the calibration results. I understand now, @dan, why throwing this out there was a command decision - this has the potential to quiet a lot of disgruntled souls AT ONCE. Quick hit/quick victory for you guys…
But PLEASE… Snapmarks? 
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No. It calculates the offset pre- and post-calibration and doesn’t make any changes unless the new calibration is better.
While this won’t hurt, it’s no longer necessary, as the process now re-homes both before and after (based on great feedback from everyone here about learnings like this!)
However, if you’re testing for accuracy, you should reboot before running the test (per the instructions).
Yes and yes.
When we investigate reports that there are still problems post-alignment, this is, by far, the most common cause!
“Quick” in the sense of “the better part of a year of R&D, including collecting thousands of data points with Snapmark to learn how to do it”. 
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I just spoke with engineering, and we just pushed an update. Now, if there’s a temporary failure during the calibration process, we will do our best to pick up from where we left off and finish. As long as we’re making progress, we’ll keep retrying.
If you haven’t been able to finish calibration before, it might be worth trying again. This will not make existing calibrations any different, so no need to re-run them.
This will reduce one of the most common reasons we’ve seen for calibration to exit without finishing - spotty network connections. If the connection is dropping frequently, we’ll still be able to finish.
(This happens to me at home sometimes when my personal Glowforge, GlowYourBoat, decides to connect to the weak signal upstairs instead of the strong one coming from next door. Rebooting the wifi clears this up.)
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Ran the calibration on my seemling perfect aligned glowforge. Left side of bed = no noticeable change (still perfect) but significantly improved the right side of the bed. Many thanks for this improvement process. The right side was so spot on I had to double check to see it actually scored the draftboard
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I didn’t have any medium draftboard on hand, so I used some thick draftboard that I had.
The alignment is noticeably improved. In Y, it is just about perfect all around the work area. In X, it is best on the left and in the center, and not as good on the right. Still better than it was before, but off by an 1/8" or so, but just on the right. Didn’t seem to make a difference if I did the accuracy crosshairs individually with setting focus in each area, or multiple scores with set focus at each location.
I will try some more tests. But is there a benefit to doing a calibration again? i.e. if I went from >1/4" off all over the place to very good in most of the spots, will I get even better if I try again? And from reading other posts, it seems like the thick vs. thin draftboard shouldn’t be an issue… but maybe I will try again with the medium when it gets here.
As per a response from dan above:
OK. but my question is… if doing the calibration once got me from bad to acceptable alignment, would doing it again go from acceptable to excellent? Or is it not worth even trying to do it again?
And, does the “set focus” adjust for lens distortion, or for workpiece distortion? (or both?) i.e. would it change from spot to spot in the work envelope if the workpiece is complete and flat to begin with? Or, is the main benefit of the focus setting in cases where the workpiece is warped, curved, or maybe has some missing areas?
I don’t comment on much and haven’t been lasering as much as I would like but so excited for this feature. One of the single greatest aspects of the GF (in my opinion) and I can finally use it to it’s potential. Thanks for addressing this!
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Can’t answer regarding multiple calibrations.
Set focus will address a couple of things, I believe: 1. Material that is warped, and 2. Inconsistencies in the flatness of the crumb tray and machine.
If everything was perfectly flat (material and tray), and the material was planed to an exact thickness - in other words, zero variability, set focus shouldn’t change anything between marks A and B.
Having no inner knowledge of the glowforge, but almost 30 years of working in embedded software my suspicion is that it is not incremental. You would not go bad to acceptable and then acceptable to excellent. If so, I would expect them to instruct users to try, try again until it was excellent. However, that doesn’t mean a second, third or fourth attempt would not get you to excellent. Based on what other people are reporting here, If I only had acceptable I would try again with a different piece of material in the middle of the day with the lights off. Middle of the day so there was plenty of ambient sunlight, but no direct sunlight on the machine. Just lots of diffuse light. At no point has glowforge made this a suggestion, much less a requirement, but I’ve been on a machine vision project and that is the best kind of light for the best results.
No comment on set focus other than if you are using a small piece of material, or one with lots of holes in it, I’d use it just so you know the glowforge will measure your material and not the crumb tray.
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i suspect @caribis2 is correct here. there may come a time when they’ve updated some algorithms and it’s time to run them again. but unless you had a user-introduced issue in the first calibration, the second should not create a better result.
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Sorry to make you wait so long, @kb2thdr! We’ve made a change on our end that should clear this up for you. You may need to run the lid camera calibrator again, however. Could you please reboot your Glowforge and try a test target print? If you continue to see the offset, please run the calibrator again.