i see, we don't yet support the feature of loading a texture that designates where the texture will be painted.
This is something we could look at sooner for you, rather than later.
I will download L3DT and see if i can sort something out.

As for your path, we do have a road system which carves through the terrain to make it smooth.
This tool can also be used to create small paths and make them smooth enough to walk on.
Edit:
if you have any files that i could use for testing, then it would save some time and allow me to get straight to programming.
