I was able to export a .ter file from the heightfield generator (to play with in WM), I've found that the most reliable way to get terrain out of TG2 so far (haven't tooled around too much). There's a plugin for 3DSMax to import .ter files as polygons, it was a I was attempting to use the Heightfield from Shader node to eek out something procedural into a .ter file, but haven't sussed out how to make that work (assuming it's possible).