Lego Star Wars: The Complete Saga

When you first get to that room there is a lever to the right pull it three times. Then jump down and go to the bottom left hand corner. Blow up the bombs in the way then move th elevator over by the push switch thing. Then jump on top of the switch then the elevator to the next side. Pull the lever over here to release a bomb. Push it down to the first level and it will blow a hole in the ground that makes a ramp. Hop into the little car down the ramp and drive to where there are 5 red buttons. Drive over the buttons so they all light up green. A bridge should appear. Hop back on the level where you droped the bomb from make sure if your in story mode to have a storm trooper hat on and go ahead and open the door.

I haven't got there either, but i think it would help if you bought Disarm Troopers at the bar and using it to turn the troopers's weapons into carrots.