Unable to use terraforming tools

[CarlosMZ12268]

So... I've just downloaded SC4Terraformer and I wished to use it to sculpt a region I previously had. However, whenever I tried to edit the ground, it would always revert to the original shape, not allowing me to terraform. When I create a new region, though, it works fine. Could anybody help me? 

[APSMS]

If any tiles are treed or have cities established, these city tiles will be locked by default. When you open a region in Terraformer, you have the option of unlocking all the tiles or just the untouched ones. Make sure all of the tiles are unlocked before you click OK to load the region, and you should be fine.