It could be really awesome, if we could make a simple thing out of it, no simply to save the terrain into .hmp after it was deformed (as it already does it perfectly), but to save and handle the texture changes as well (it's not so hard I think). And this could be very useful around the forum (I'll probably upload it to my website as well).
its dll does not handle texture changes, I save them in outer files. for that purpose you should do your own dll by the SDK. to be honest, saving as hmp is not a must in case of a game, you can save simply its vertex height values to a text file. I do it as an alternate solution and works fast.