Help with Megascans!

So, I have downloaded the free Sandstone Rock from Megascans.

I have the settings set to Offline rendering, resolution 8k, tris 7,000 and all the rest are default. Now when I am texturing the rock I can’t see any of the moss on the rock at all. I am using the albedo maps, normal maps, displacement maps and roughness maps since I don’t know how to use the fuzz and cavity map, (if anyone knows please let me know!) So does anyone know why I can’t see any of the detail?

You didn’t even tell us which render engine you’re using… BI? Cycles?
At least show us your material/node setups - otherwise we’re flying completely blind here!

This is what I get with 4K maps:

https://dl.dropboxusercontent.com/u/27650383/27-08-2016%2023-46-12.png