Just watched it. Interesting. Your passion for the original film comes through very clearly.
Suggestions:
* Most of your actual script was great. I'd polish some of the ship computer's wording, though. Phrases like, "I'm listening," "Fire away" and, "Give it up," are too informal and not the type of language I could imagine a Mother-alike using.
* Why did the ship refuse to allow the crew to evacuate if the mission was to retrieve the creature? It didn't require them to achieve that objective.
* Higher definition cameras would have helped a lot, but especially so for the picture of the planets at the start. The lack of sharpness to that image didn't sell me, as a viewer, on it being a real space environment.
* Use more than two camera angles for the table discussions! Have the actors replay the same discussion and shoot it from different angles and different zoom levels, if you need to. Look at the original film and notice when there are close-ups of Parker, Lambert and so on and for which reasons (Lambert inhaling from a cigarette and so on). The same two camera angles made that feel static.
* This is a flaw of many fan-films, but there was too much self-awareness of the actors, at some points. Some felt nice and natural, but others looked slightly awkward.
* The characters shouldn't be feeling so tense, initially, during the duct sequence. You have them later realise, in the script, that the creature has grown, but up until then they should just be assuming it's still pest-sized and not much of a cause for alarm. Allow their lack of awareness (possibly even arrogance) to drive the tension for the audience, until nightmarish reality begins to dawn upon them, Brett-style.
* There needs to be a reason why whichever character is acting as the medical authority hasn't scanned the facehugger's victim and realised something is gestating. Ash did, after all!
* I would avoid all references to the Sulaco. Just allow it to be an ambiguous, unknown wreck. This saves you from having to work in the 'Bishop-did-it' theory and devote more time to the story of your own characters.
* Don't allow your love of the original film to dictate events. Too much time was spent on trying to directly mirror the original film's events (right down to the inclusion of that fanous airlock scene). This is fine if you're undertaking a fan-made remake, but otherwise can make the viewer feel as if they're treading water. Diversify your story into being more original!
You clearly have the talent and it's a shame you aren't allowing your story to be its own thing more.
* Hand-held camera-shake is fine to emulate vibration, but not when you're attempting to show smoothly gliding spaceships. Place the model or the camera on either wire/rail-guides or, more cheaply, mount them on top of a wheeled toy and pull them along with wire. This is a cheap and easy way of creating a 'dolly' effect and will enrich the motion effect you're going for. Even the slightest shake will cause the audience to remember you're using models, instead of helping to create willing suspension of disbelief.
