How did the engineer enter the locked ship?

This question has been edited a bunch of times. I'll try and break it down:

During the last scene in Prometheus, how did the Engineer enter the ship after Dr.Shaw had locked the doors?

Brute force I guess - he was also able to rip an android's head off. This may be something to come in a future director's cut, as I think a few minutes of fight scene were edited-out between the Engineer arriving at the pod and Shaw opening the inner door to the squid-thing (possibly to avoid an R/18 rating).

I'm also not sure that she actually locked the external doors, just closed the air-lock door.

And how come the engineer came without the mask?

Early on they state that the atmosphere is almost breathable, but with toxic levels of CO2. maybe the Engineer has a higher tolerance to CO2, or maybe he could hold his breath for the fairly short walk from the crashed ship to the life-pod.

Also, what is that floating ball device which creates holographic maps from in the engineers ship?

Fifield (the geologist) brought the floating red balls in order to map the location - it sounds like they are standard kit for mapping caves or similar. Fifield refers to them has his 'pups'. They create the holographic map of the Engineer's pyramid on-board the Prometheus.

(and how come it floats)?

Not a clue. They have faster than light travel, almost-human androids and suspended animation. I figure they have some advanced space tech in there.

and what is that map like shown in the engineers ship ?

The map inside the Engineer's ship appears to be some kind of holographic orrery, though I don't think it maps to just one system or to scale. I'm not sure whether that includes some kind of Kinect-like gesture interface or whether David just appears to touch the map of the Earth.