I loved the workprint! My face was like... 8-O
Anyway, I think the skintones are too yelow, maybe adjusting the Hue you can fix this. And the general picture needs a little more contrast, I think...
About the opening titles, I think that 20th century logo is too yelow and too bright. Here is my sugestion:
The Lucasfilm logo is not so good as your the preview on youtube.
*Things that I loved: no more-> crushed blacks, lobster-men, blue tinted walls (Tantive IV), red tinted sand (Tatooine), "Look sir droids" scene & "Mos Eisley spaceport" scene.