I'm pretty sure something this complex came from a higher order being. That whole order from chaos argument is not holding water for me with this degree of complexity.
I see the opposite: the DNA/RNA/protein mechanism is just a gigantic pile of self-interacting hacks — core "design constraints" being that the cell: (1) shouldn't die too quickly; and, (2) should be reasonably energy efficient (due to competition).
I'm afraid your intuition about complexity misleads you here. If you'd like to learn more, spend some time with say evolutionary algorithms. It's not a big time commitment; playing around for a couple days will likely be enough. You'll find how the crap an evolution-style search comes up with is really similar to how nature works: a few beautiful core finds + a big pile of hacks of varying craziness, some of them totally bonkers, and quite a bit of insane reuse of things one would never consider reusing.
No idea, but the math says there have to be way more dimensions than we can interact with, so I'm thinking it's a higher dimensional being that we can't interact with. It/they would have to enter our dimension to communicate with us.