Warning! This page contains the complete solution or walk-through to this game. Reading this page can spoil the challenge to complete the game by yourself. Please consider this when reading on. The walk-through of this game given here might not be the optimal solution, it’s a solution. Just to prove that the game can be finished. If you want a section of the walk-through or just a hint, send us an email with the part where you’re stuck, we’ll send you the section of the page you’ll need.
Look through the vizer at planet earth.
read through the pages of your mission briefing and after page 7 select to begin the mission. You’re beamed to the landing zone. Mika is also there but invisible. Use the grape laser from your inventory on the core processing unit with the exclamation mark on the motion sensor array on the right.
You then let M unlock and open the doors and you’ll fall through the trapdoor behind it into a cell. Use the skeleton on the floor to take a BONE from him and use the bone on the loose stones on the north wall. When you wake up again, you notice the KEYCARD in your inventory. Use the keycard on the slot left of the door on the right to see what lies behind it…
Game source: A copy of the game was found here  on the internet.