Terraformer?

Hi, I don't really need a mega terrain, but I do need the ability to import a heightmap. I see that you can do this in the mega terrrain stuff, but I have yet to find it in the normal terrain. I alreay have an atlas version, and would much rather go with the legacy terrain if possible. The docs say that the way to do this is through the terraformer, but it appears that the terraformer has been disabled. How do I gen a legacy terrain using a heightmap?