I saw it on pirated DVD recently. The translation was sub-par, so I swiched the overdub off and watched it in English. I think it's important to not watch movies like this as some sort of fanboy. It was entertaining and I was somewhat emotionally involved since I've seen the Alien flicks. A work of art it is not. But it is better than what is out there right now. As the movie is meant to do, it raises even more questions while teasing you with the answers to your pre-existing ones. I did notice how a woman with a Caesarian/abortion ran an awful lot with staples in her stomach. With that in mind I expected her to die from the bleeding. But since this was already covered, I have some questions of my own.
How did David know that the Engineers were headed back to Earth to wipe everyone out? When he was in the 'map room', he specifically located Earth and grabbed it. That was why it appeared near the chair. He obviously knows something he didn't reveal, and/or sought to manupulate the humans into destroying the alien ship. Why?
What did David say to the Engineer that made him immediately turn hostile? We know the Engineer understood it, because he perked up when David spoke, but seemingly didn't understand English. The linguist hired for the film (he's the man who appears as David's language coach in the Karakul hat) translated it online: 'This man is here because he does not want to die. He believes you can give him more life’. According to the same source, there was an extended dialogue between David and the Engineer which was cut, but will be restored for the DVD release.
The surviving Engineer was asleep for at least 2000 years (the carbon sample from the dead Engineer dated that far). They woke him, and here were mutants according to his viewpoint, and it immediately became obvious that his crew was killed and that the bio-weapons were exposed. What did he do? I don't think he was headed to Earth on a kill mission. He was going home to warn his people of the danger not only of the exposed bio-weapons, but that one of their experiments have evolved so much that they were now visiting the bio-weapons storage facility and posing an unknown threat. David is the only source we have that they were heading to Earth. Also, is the 2000 year gap related to the crucifiction of Jesus?
The planets are not the same as in Alien. In Alien, the planet was LV-426. In Prometheus, the planet is LV-223. The prominent headlands in Prometheus do not match the rocky planet in Alien. Also, there were several other 'pyramids' on LV-223 which were not found in Alien. The ship in Alien featured a dead Engineer with his chest burst open. However, in Prometheus, the Engineer suffered that fate on the humans' lifeboat.
Why did David seem to want to go to Earth? Was he programmed to deliver the specimen at all costs even if his 'father' died? It seemed he was ambivalent about going where Shaw wanted - to make more contact with the Engineers.