if instead trees and grass you have polygonal mess on your screen, do next:

1) download 3D-Analyze from
http://www.tommti-systems.com/main-Dateien/files.html

2) install and launch it

3) click "Select" and choose executable of the game

4) in "Hardware Limits (cap bits)" group of checkboxes CHECK "emulate HW TnL caps"

5) click "Run"

Enjoy!


--
Andrew Rybenkov