As long as you add a disclaimer saying you don't own blockland then it would be no different then being sued by a camera company for using their camera to film.
First of all, that's not the same thing at all. You pay to use their camera's. You buy their film. Their logo goes at the end of your movie so they get free advertisement.
We're ripping off a movie, and not changing names. Only because of comical effect, but still, if we even did anything remotely close to a transaction of legal tender using Lucas' property, I would not feel good about it what so ever. Even if it were legal, it feels wrong to steal ideas. I guess as a creator myself, I understand the need for copyrights.
No thank you, but it was nice of you to try and help.