This version does not include Aliens or any other new creature. The names of the creatures will NOT match their appearance.
If you want the complete (and finished) mod with Facehuggers, Aliens, Nostromo interior and other stuff, you have to contact me. Write a PM is the fastest way.
Just say you would like to have it and you get the link.

Text from readme:
Enter the Nostromo with: coc nostromo (you can also fast travel from here back to tamriel)
Pick up the helmet there and equip the space-suit before you go through the door to explore the moon Acheron (LV-426).
Acheron is very dark. It has no stars and is covert in a very thick dust cloud. Bring light with you.
Be careful to not fall into a canyon, you might not get out again.
If you enter any derelict spaceship of unknown origin - don't touch any green glowing containers!!!
But I know you will touch them anyway ;)
This does change root caves of the Shivering Isles, but if you don't mind having the rootcave textures of this mod, it should be no problem.
But if you visit the Isles, I sugest to deactivate this mod first to see the normal cave textures.
Have fun and be well prepared!