And the invulnerability, I assume.
These screenshots look like a marked improvement over the last of your levels that I saw - I forget which one, but never mind...
Although not perfect (which I guess is a matter of opinion anyway) the texture schemes are pretty good... there is one thing I don't like in the second screenshot though - see that bright blue patch of floor next to the yellow door? It contrasts rather badly with the neighbouring grey floor and ends up looking ugly.
When you're working with rock textures, at the very least, you need to ensure that if you have any seams like that, they aren't too pronounced. Alternatively you can use metal borders to solve it - like what you've done for the deep blue rock just above, where it meets the roof of the neighbouring hallway. Just be sparing with them, or else the level starts to look like a construction site.
Actually, if I were you I'd just reduce the number of textures visible in that place - I count nine types of rock in the same scene there. It makes it look a little too garish, if you know what I mean...
But apart from all that, the texturing in the majority of the shots is good. I personally don't like to change textures at points along a flat surface, but that's just me and you might have different ideas.
While most of the structure is a bit simple, it's no big deal until you start to get comfortable with doing really weird geometry. The energy centre there is pretty neat, too.
But it is looking good! Even if all those comments don't make it sound like it...
