I edited through chapter 29, which is as far as I've written.
I feel a little ergh about the first draft--the first section is great, but that's because [SPOILER] is happening, so there's kind of a natural story arc. The problem is that after [SPOILER] is [SPOILER]ed, things start to wander a bit. So I need to ramp up the tension a little, which I think should be doable, since [SPOILER] happens next--I just need to rework that part so that its full impact is felt, which isn't happening right now because [SPOILER SPOILER SPOILER].
In addition, you can tell that there was a long interruption to writing it, because some of the much later chapters read like I'm trying to introduce the whole fictional world all over again. So that needs work before I push on.