I have a quick update on this game, turns out the launcher settings are bugged , and you will have to force GPU PhysX on through ini modification :
My Games\Rise Of The Triad\ROTTGame\Config\ROTTGame.ini
and force bPhysXEnabled=true
After which , several objects and walls will have destructible pieces and debris, as well as a big number of rocket explosion debris.
Also it seems the game developer was collaborating with NVIDIA in integrating PhysX, see this video:http://youtu.be/U-4BPApx9Jk?t=2m58s