The Death Star schematic was done in POVray. The original schematic was removed automatically for most of the shot, though I had to do it manually for a few frames as it began to interact with the lines at the edge of the projection. It took a while, but I managed to line up the solid square in my schematic with the zooming-in square of the original, and made a fade of a few frames between them. That was the only 3D work I did for ANH.
"Invisiben" was done by taking Ben's face out of another shot from the duel (at least, I think it was - it may have been from the scene in his home on Tatooine) and pasting it in (there was some subpixel tracking to match it with the falling cloak).
Zion, hopefully you're reading this - my PM box is full, so email me at dartheditous(at)hotmail(dot)co(dot)uk and I'll send that thing to you.
Any other questions?
DE