Export the terrain as a height map and apply it as a base mesh material to a Relief Object. Then you can texture it to your heart's content. If memory serves (often it doesn't - usually around birthdays it does this...) you can click Function>Current State to Object and edit just like any other object (extrude polys, push/pull areas, create overhangs, etc.).

I've gotta try that just to make sure... Plsu it would be fun to mess with...

I usually do my modelling of objects and props and bring the INTO Vue for the landscape part and rendering, not the other way around.

Keep in mind you'll need it to be a fairly high poly-count (more than the something like 20x20 it starts with when you first create it) to begin with unless you don't mind some jaggie edges - a normal map and a bump map will often hide this just fine - think of game art that looks smooth - it's deceptively low-poly.

Good luck - hope this helps-
-Lew ;-)