The closest thing to a contribution I ever did was make mock up videos to share ideas. The only one I recall being used was the fix of the abrupt stop of the backward floating Millennium Falcon among the garbage. Though I'm still hoping Ady liked the lightsaber sparks idea, so that Vader's lightsaber hitting the floor would be consistent with the rest of the film. I also remember adding a saber-hitting-surface sound effect to go with it.

Unfortunately, I think just about all my mockups were removed from youtube!

But anyway, it doesn't necessarily bother me if names aren't added to the credits. I just want to see it released! Can't wait.