Alright, here's the last part:
Place the beacon on the red marker.
Then use the lift that's right beside you after the cutscene. Then go back into the main building, an use the lifts to go down this time.
Use the lift on the catwalk.
Circle around and plant the last beacon.
Use the lifts to go back up, and then go to the command center, pictured here.
To get inside inside, and use this lift that's in the wall to go up. Ignore all the baddies, and plant the last beacon.
After that, go out the door in front of you, and you'll see the Imps in the distance, go to them, kill them, and shut off the first bomb.
Continue going around counter-clockwise to eleminate all the other bombs.
After you're finished, go back to the hanger and to your ship for end level.
Was a very good day IMO.... got all T1 and some of T2 done