To unlock the T.T. door, you have to complete EVERYTHING! What I mean is that you have to collect all of the trophies, keys, Wizpig pieces, and T.T. pieces. Once you do that, go to where the lighthouse is. it won't be there anymore. drive on to the platform and that will transport you to the T.T. room. What it is, is a place with extra levels to do, and the boss of the room is Wizpig. It is hell of a lot harder than last time. He rides a rocket instead of running, and there are like a million bullets shooting out at you in many directions. But the side of the difficulty of the room races, it's a lot of fun. There's the answer to your question. Have fun! =)

i dont have an answer but i did all the keys and stuff.... its still there! do ih ave to beat wizpig for the first time also to make the lighthouse dissapear?