I've got all the Borderlands DLC.
Well I think I do.
I've downloaded it... it shows up as DLC that I own in the main menu of the game...
But it's never reared it's head while I've been playing the game.
No Underdome. No Island of Doctor Ned (or was it Zed), no Secret Armoury...
Is there a reason it's not showing up in my game?