Use the console in the middle of the room, and then look right at the frozen wall. Use Force Push on it to break it for another secret area.
Use the other lift, go down and clear the room, then go out the door.
Waste the guys here, and then go through the other door.
Go around the room, and go through the next door.
Kill these Imps, then use the lift.
Kill these StormTroopers, then go outside.
Use the E-WEB to kill all the troopers, then follow the beacons as you mention.
Hop over the AT-AT hulk, kill the baddies, then look at the force field. Blast the little thing beside the beacon, and it'll shut off.
Go down and jump into the hole for end level.