So I rescued the T'rang and the Umpani from the Rapax, ran around to talk to the bosses on both sides, got the T'rang tracking device and am now standing in front of the controls (I think) for the big gun that'll knock out the Dark Savant's ship.

Problem is, it's asking me for a Control Code and...I have no clue what the control code is.

Sounds like you are at the console in the room which is the wrong device. When you come out of the elevator, go to the missile launcher towards your left, use the tracking device and watch the results.

Ah, ok, was thinking there'd be a console or something near the missile. Maybe I just missed it, thanks.

Use it on the orange button on the panel below the rocket.

Oru