My nitpicks are as numerically proceeds:
1) The battle androids are without infrared or long-distance vision, apparently. They appear not to notice Cain, who is not even ten feet away from them. This makes little sense to me, considering they would presumably be advanced beyond human strength and ability.
2) How did the female android (Alicia) locate Cain after he trekked so far away from the cabin when he decided to learn of what became of the humankind?
3) A battle android notifies that the infiltrators are heading in an easternly direction and not concisely eastern. Can androids not meticulously calculate distances and determine directions?
You can't start a whole race from just two people. It's a nice story, but that's all it is, a story.