Greencapt, I'm glad someone agrees with me about Lando's role. I've talked to so many people who dismiss him as a traitor, having lost his way and only realizing how stupid he was when everything went to pot. But I really think he was looking out for the greater good. Like you said, almost everyone else would have done the same thing. For one, if Vader comes to your city and tells you to do something, you do it. That city could have been destroyed so easily if he had resisted. He had a responsibility to the people he governed. And he was promised that, if he agreed, the Empire would be kept out forever. And he was originally promised that Han, Leia, and Chewie would be completely alright. They were just being captured to lure this Skywalker person in, and once Vader had gotten what he wanted, he would leave. His city would be alright, and his friends would be alright. Once he saw that he no longer had any control, everything was spiraling into chaos, and Vader was completely untrustworthy, he realized that he had no choice but to put an end to this. His continued complacency in the face of unjust acts was making things worse and worse.

Like you said, complex characters with human emotions!