is HiTech accepting MA terrains with altered ground textures now?
Straight from Skuzzy in 2006 of what can be customized for MA terrains (still stickied in the TE forum):
1) editing terrain textures
Yes2) rearranging the object layout of the default terrain clutter tiles
Yes
3) replacing terrain objects (like trees or forrests) with custom objects on the clutter tiles
No
4) editing default object textures
Depends. One of the goals of a MA terrain is to keep the size reasonably small. Changing a lot of textures have the greatest imapct on terrain file size.
5) rearranging the object layout of the bases or strats
No
6) replacing base or strat objects with custom objects
No
7) adding new objects
No