Ahh you played it! :D IM really happy to hear that! If I remember correctly teh controls are roughly:
WASD to move and mouse to look around (superflous I guess)
Tab to change unit
Z,R,E, 1,2,3,4 to reload weapons. you have to remove the magazine, Z, pres a number to get a new one up, then insert it with E and chamber it with R
You can give orders by looking at the map