From the manual:
Your missions: Destroy the enemy forces and rescue as many POWs as possible.
It seems that the bad guys have set up shop in five key sections of Majipoors's dense jungle. Beware of armed soldiers stationed in the trees and situated on top of watchtowers. Small platforms of solid ground dotted throughout the undergrowth should be used as landing sites from where you can pick up survivors.
Intelligence sources suggest that a large battleship is docked somewhere on Majipoor. Needless to say, if you see it, destroy as much of it as possible.
We think your buddy is being held in a ruined temple deep in the heart of the jungle. Get to it, get him and any other hostages, and then get out in one piece. That's all.