Can you use your own materials and textures?
Yes! This is one of the main feature - LAM it's flexible tool to use it with your content
How will it look on generated mountains?
Sample of mountain generated in WorldMachine:
What about FPS?
Turned on bForceDynamiclight, system specs: GTX 680, core i7 3.40, 16gb,
Can I use assets from the pack in commercical projects?
Yes, you can!
Is this suitable for different environments (moon, snow, ice, volcano, jungle)?
Yes. This is an universal tool for any landscape topology
Did the assets have LODs?
Yes they have LODs. For the sample:
Lods for grass - 3 (94 \ 52 \ 32 vertices)
For bushes 1 lod ~20 vertices
For flowers+grass - 3 lods (246, 206, 140 vertices)
Leave tree 3 lods (35k, 4k, billboard turned off by default)
How to change size of the grass meshes?
You can use min and max scale preferences in Grass Type properties.
For example: /Game/LandscapeAutoMaterial/Meshes/Grass/Grass_01.Grass_01