I've already mentioned Vader's swipe at Luke... To me it almost seemed like he is using the force push on Luke, and the light saber is just swiped in an symbolical manner, the same way as later when Vader throws stuff at Luke in the corridor scene. But it is all very short and unclear, so we can all think what we want to I guess...
I am constantly amazed by the level of effort and profesionalism of Adywan, great job on the new clip, can't wait for the new trailer!