I listened to the commentary last night but forgot a few things but im going to give it a listen later
Jon Spaiht talked of his script.
It began with the introduction to a UFO arriving on Earth and these engineers talking to one another and one drinks the liquid, evaporates and his mutating DNA cells are blown all over the surrounding valley whilst the rest of his mutating cells drop into the water. Some of the cells land on an early ape like tribe of humans and they begin to mutate.
His script then cuts to Mars where Shaw and Holloway (Holloway is an older man maybe in his forties who was Shaw's teacher) and they find a cave, basically the same scene as in the film except its on mars.
He also wrote several ideas for this in his drafts. one was they find an underwater city dating back 35,000 years ago (Atlantis?) and find the cave.
They then travel to Mr Weylands office on a space station orbiting Earth (another idea was they went to his office on mars) and talk with Weyland with vickers and David nearby and talk about organizing a mission.
They travel to LV-426 and find a pyramid there and enter it and some of the same scenes happen from dan O'Bannons script. They travel into another structure which is actually the Derelict. There is xeno's, Eggs, Morphing and Shaw gets attacked by a facehugger and she manually performs a C-section and removes the chestburster while its still premature.
They awaken the engineer and the same stuff happens what was in the film. The ship crashes into the Derelict causing it to fall.
Not much else was said from Jon spaihts.
Damon Lindelof kept the same beginning scene from Jon intact but took away the fact that it was Earth and took away any indigenous lifeforms.
He kept Jon's shaw + holloway introduction but placed it on Earth. He changed Holloway to a young man and made him more cocky.
He came up with the dream sequence and a few cool ideas such as David interacting with Weyland through an artificial memory database.
He never had the Weyland hologram spech in his script but decided to put it in because he didn't know how to tell the audience where and why they were heading story wise but claimed he didn't want to do it because he hates Composition and hates making characters explain things.
He changed it from LV-426 to LV-223 which he claims is a LONG LONG way from LV-426 and is not even close to it.
He then re-wrote the dialogue and re-wrote everything Jon wrote by taking out any 'Alien' creatures. Jon's script led directly to Alien and Damons script led directly to a new franchise. From the way Jon talked he described his script would need a massive budget. Damon's script was more confined and claustrophobic so needed a lesser budget but he describes that if all of his script would be a 3 hour film basically.
so a lot got cut or changed from his script. Damon also revealed that Ridley cut or didnt use a lot of material that built characters because he felt it was better to just get straight to the point and not waste time
I'll listen to it again tonight as my senses will be more aware and I'll take notes of everything they say.
A really good commentary and It hurts me to say it but it's better than Ridley's because he only talks about the technical aspects of the film rather than the story itself.