Haha, I knew it! We sat on our mods for months, expecting them to be incompatible with the new editor, but under the surface lying the possibility, waiting for its revelation.
I used some old templates for my LivingWorld mod and saw them working; same with the IDs of all the game objects. So I got an idea from that...
Thank you for figuring this out and showing how to make it work! Fantastic that it's possible to transfer our long resting maps!