Honestly, I can't grasp your workflow. When I performed tests earlier in this thread, I used an image, imported into MC specifically to test the saving of the edited image. I did not touch the album art side of the issue.
What would help is if you could lay out, sequentially, step by step, the process you are following, starting with:
1. Download file from fanart.tv
2. ?
all the way through to the end.
Then you may receive better advice or bug confirmation.
I think I've found the source of the problem.
I copied a 1000x1000 fanart.tv cover art and pasted from clipboard onto album.
I then edited the art to 500x500 in MC32 and saved and exited.
I then saved cover art to location in settings.
My settings in MC32 are set to save cover art in the same folder as the file and in the tag.
In MC32 cover art edit it shows the file as 500x500 but in the album folder it saved at 1000x1000 original.
However, the default folder setting in MC32 is appdata\roaming\JRiver etc.
This setting is also in the cover art pop up after editing cover art.
If I look at the appdata\roaming\jriver etc folder it also saved at original 1000x1000.
I then changed the cover art folder option in MC32 to a cover art folder in my laptops pictures folder but left MC32 to save cover art to the same folder as file and tag.
After I did that and repasted the 1000x1000 cover art and then edited to 500x500 in MC32 it properly saved in the album folder and tag at 500x500.
You'll notice that even if you change default cover art folder to another one in MC32 settings, the cover art edit pop up still shows default appdata\roaming one.
So their is probably a bug in MC32 that prevents cover art from saving at edited size if the default appdata\roaming\jriver folder is selected and you choose to save cover art in same folder as the file and tag.
Try it and see.
My screenshots show the options that work.
If you change MC32 settings to default appdata\roaming\jriver and choose save cover art to same folder as file and tag it won't save at edited size for me.