Quote - First of all it depends on what you are placing the displacements on.  Is it a terrain, primitive or imported object. Terrains and imports take a bit more doing....

There is the quality slider to the right of the displacement check box.....try different settings there.

Jeez I can't believe I overlooked the quality slider...yes it works now, with very high-poly displacement indeed. What a shame.

What I do is sculpting objects from C4D to a pretty rough shape and displace them in Vue deeply. Your rockset kinda inspired me to do my own :D