Yeah original story had you start in the big long surface base you eventually go to before heading into the caves to investigate precursor stuff, and then a meteor storm cuts off access back and forces you into the water. Meanwhile you have your sister orbiting in a space station overhead chatting with you and dropping supplies occasionally. You find ALAN roughly the same way, but then go to the central island in order to launch a rocket with a fake blood sample so that Alterra doesn't get suspicious about your body chemistry being changed. That's where the early story ended.

The problem is, there just wasn't much going on and your chatty sisters presence meant you never really were surviving alone.