6: Goo?
The black goo is bad, I got that. But what was the black goo? Was it different from the other goo David was touching? Where did that other goo come from? Obviously it was there to make you think of the stuff that a Xenomorph leaves behind but why is it there? It makes no sense!
7: What's The Emergency?
What were the Engineers running from in the recordings? It's not explained in anyway. Did something go wrong with the goo? We just see them running into a chamber. What was so urgent that one of them ended up decapitated? None of this is explained because the writers don't know. It's just stuff that happens.