1. Ensure you have protontricks installed. If you don't have it, follow the installation guide here[0] (see the pipx titled section)

2. Go to "Distant World 2" properties, force a specific proton version, select Version "Proton 4.11-13" or anything old enough to still support dotnet45 which is broken in many newer releases (incompatible versions of proton will give a related message and fail to install dotnet)

3. afterwards, install the game like you would normally do

4. Try to start the game, to let first time setup run which should install 3/3 packages of software by itself before launching

5. Launcher opens, if you click "Play" there most likely nothing happens, that is okay

6. Open a terminal and run:

   protontricks --no-background-wineserver 1531540 dotnet472

   This will take a quite while, do some downloads and show you maybe half a dozen of windows installation dialogs for different versions of the netframework, starting from 4.0 going all up to 4.72, as the newer versions depend on the older ones. Be sure not to cancel any of them and endure accepting all of Microsoft stupid licenses while installing the software packages ;)

7. Once dotnet 4.72 is fully installed, launch your game again. This time, clicking "Play" in the Launcher should actually opening the game.

[0] https://github.com/Matoking/protontricks