That's an elegant solution, Patrick. Another idea would be to convert to vertex model, and knife off the bottom by making a boolean with a large cube. And another possible work-around....Anything Grooves includes a "zero is empty" checkbox. So you could set up the terrain in the Terrain Modeler, export the grayscale, apply that as texture to an Anything Grooves object, and turn on the clipping. I also came through Bryce, via more of a roundabout way, and I wasted a bunch of time looking for that oh-so-useful "clip" button in Carrara. Of course, Bryce had adjustable top and bottom clipping (even better!)