That's one hell of a start. Excellent idea! Original feel to the story and some actual tension building moments! This has some real potential!
I really liked how it's going, but the only "negative" aspect for me is that this story is more or less linear, since there's not much to choose at all, and the options when they exist, are non canon.
Anyways, it is good, and very well written. Waiting for chap2 ~
Good style and writing. Very much interested to see the next chapter.