For terrains you will just need the textures.
In the terrainbank folder, copy one of the folders and rename it to your liking.
Find seamless textures you want to use for your road textures. (Striping lines will not be good for this)
Do you have the .dds plug in for GIMP? Do you have the photo normal map plugin also?
That will be the output of the files you want.
Open the textures in GIMP.
You will need to save these files to the names in the folder you copied over. Keep the same names, different textures.
For the _D textures:
Apply a layer mask for greyscale copy of the layer, and apply it.
This will make the texture transparent. Dont sweat that yet.
Save as using .dds format in the DXT5 compression.
For the _N textures:
You can use a photo normal map plugin to generate these from the Textures you found for your terrain.
Save these in .dds format with DXT1 compression.
The detail map is a greyscale copy of your default texture, then apply a greyscale layer mask to it.
Save this file at .dds format with DXT5 compression.
Erase the superpalet.ter file.
Open Game Guru and run a test game. Go into the metrics panel and choose your new terrain as the choice.
It will generate and then you should have your new terrain working.
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