Good job Celludriel!
I have a lot of patch files created in my terrain folder. In this case I tried selecting the first one but it doesn't work.
Tested with a 8x8 terrain.
Can you get me the terrain patch and data file together with your heightmap ? I'll try to reproduce why it wouldn't work for you.
Also make sure you are in the \Data\Editor\Mods directory. I made the mistake not being in the Editor folder the first time and it didn't seem to work either then.
Also each terrain gets an unique UUID, that long weird text thing. You should be able to find that in the divinity editor as well if you click on the properties of your terrain. Make sure you pick that file.
