Just another theory..

I was thinking maybe the temple is an old abandoned alien factory where they create life and the space jockeys deliver them to planets out there in the universe. Maybe the lifeforms are stored into the urns and are taken and shipped out. The forbidden fire could be the technologies that create life. David could have messed around with the controls where it wakes up a space jockey, the jockey gets the information and is like oh ok, my mission is to ship this to earth and it might be something really unpleasant.. Hopfully the spacejockeys are just servants to something alot larger and mysterious. So this can still continue and alot of gigers work is brought to life. The nasty stuff killing the explorers could be dangerous experiments that may have broke free lingering around the palce or let lose accidently by the crew.