Patience, my friend 
I’ll let you know when I have the time to take a closer look.
In the meantime, if you set “metadata synchronisation” to read-only in preferences, art will not mess with your xmp, so the tags won’t be touched even if they are not displayed correctly. (In general, setting the option to read-only is recommended if you are using an external app to manage your metadata.)
No hurry 
I guess the option you mentioned is already set to read only. I guess that’s the default.
should work now in the latest master
Wow. Great. Is this the file I should be downloading? ART_master_1.8.2-224-g0f682e0d3_W64_generic_211108.7z? Or something else?
Have pinged gaaned92 few days back. Haven’t got any response from him.
Sorry, I just come back today from a stay in south of France.
Before leaving, I was no longer able to make a working build!
I have to try again and will report. @agriggio Surely I will need some help from you.
André
Here’s a windows build of the current master:
https://drive.google.com/file/d/1OrkjrTfsnU5wNMym-sQENS2HiUOSJem3/view?usp=sharing
HTH
@agriggio, @gaaned92 Thanks for the updated version. Downloaded it. Couple of observations as follows:
I don’t know whether this is a GIMP problem or an ART problem. Thought will let you know. Any help in sorting out this will be great. Essentially, I am trying to create a workflow where the tags are seamlessly passed from digiKam to ART to GIMP and back to digiKam.
Sending you the screenshots
ART 02 .jpg - Screenshot from ART showing tags read correctly
digiKam 02.jpg - Screenshot showing tags combined by GIMP as one tag
Dropbox link: Dropbox - ART - Simplify your life
Hi,
the tags occur multiple times in the xmp file you shared, listed under different xmp namespaces. When using exiv2 to import them to IPTC keywords, they get duplicated. ART filters out the duplicates, I suspect GIMP behaves similarly to exiv2. On any case, if you set ART metadata synchronization to read-only, ART should not mess with your tags ever…
I have set GIMP as an external editor in ART. What format is passed to GIMP from ART? Is it tiff or jpg? Also, if ART filters out the extra tags, where does GIMP get this information? I have set the metadata synchronization to read only. I would like GIMP to read the tags correctly.
ART doesn’t display duplicate tags, but if there are duplicates, they get copied to the output. I will see if I can change the behaviour.
I thought as much. it will be great if you can suppress the duplicate tags in the output file. Is the output file in the tiff format?
Now I need to figure out how to prevent GIMP from merging all the tags in one tag 
New version (what will probably become 1.11):
https://drive.google.com/file/d/1nNSb3eGoWs-HUjORnCjDTZl_sFsjcRgo/view?usp=drivesdk
Thanks for the update. Did a quick test. The tags are not repeated multiple times now. However, for some strange reason I see a tag containing all the tags in GIMP! The tags are separated by comma. Don’t know whether it’s a GIMP problem or something can be done in ART to prevent this. Again uploading a screenshot ( ART03.jpg) to Dropbox for your information.
Hi,
did you check with exiftool and/or exiv2?
If yes, and if their output is suspicious, then I’ll have a look. Otherwise, I’d consider this a GIMP issue.
Did a bit more digging in the way GIMP works. Same thing used to happen when GIMP used to create a tiff output file. However, if I unselect the option of saving xmp data GIMP does not combine the tags in one tag. Perhaps there is a clue there! If ART can suppress the xmp data in the file it sends to GIMP things would work seamlessly! Hopefully!! Thanks for your patience and support. Appreciate it a lot. Uploaded a screenshot of the output options in GIMP.
If the metadata that ART generates are correct, this is a problem on the GIMP side, and “fixing” it on the ART side is not the way to go.
On the other hand, as I wrote above, if you have evidence that ART generates wrong metadata, then I’m certainly willing to fix this.
HTH
It’s hard for me to say where the problem lies. I created a tiff file from within ART and checked the metadata using ExifT ool. However, not being very conversant with how different programs treat metadata, am unable to pinpoint the source of the error. I am assuming that the tiff file sent to GIMP from within ART is the same file which ART saves through the “Save current image” option. I am have uploaded the tiff file. If you feel like it you can check the metadata generated by ART for that file. It’s not a showstopper. However, if it works out, my work flow is that much more streamlined.
The metadata exported from the ExifTool is attached below.
Again, I would not insist on you spending more time on this problem. For me it is more of an academic curiosity!
Looks like the version 1.11 is out! 
Any difference between the version you shared with me? I have a 9th generation CPU which I think is Coffee Lake. Since I do not see this listed, I guess I should be downloading the generic version.
I am using the portable version. Should I just unzip the archive in the program directory?