If your game is unpacked, just extract the DMTL to your game folder. (My source was unpacked.)
If your game version has a packed executable, you need to unpack it first.
You can do this by using the "EnigmaVBUnpacker". I will add a version as an attachment.
Just start the "EnigmaVBUnpacker.exe" choose the location of the game executable and click on "unpack". Please verify that this step worked correctly by launching the unpacked game once using the "Game.exe" inside the newly created folder "%DEFAULTFOLDER%" before merging my MTL into it.
Should you just get a white screen on startup, rename the "%DEFAULTFOLDER%" to "DEFAULTFOLDER" and try again.
