This is probably the place Neptune came from:

http://originaltrilogy.com/forum/topic.cfm/Star-Wars-3D-Conversion/topic/12312/

The 2d-3d conversions sorta work. But are not a good representation of the technology, according to the members there.

*EDIT*

Ok I see they've branched out into another forum. The first clue of what they are doing is the following:

In the first phase of our conversion process unfortunately, there's not much that can be done yet for adjustment of depth. The second phase (frame advance on one side) can add some depth but it is motion dependent. We usually run the frame advance either for right to left or left to right. It could be done scene by scene but that would take alot longer. As it is now, it's an imperfect process. One could try swapping fields while viewing and play with dropping the horizontal parallax back a bit based on the scene. (these adjustments are available in Stereoscopic Player and Stereo Movie Maker).