Get generator code from primary terminal in control room.Find the underground tunnels at the waterdam.Help the Duty checkpoint - Kill the boars.Get information about Strelok from Mole.Rescue novice and retrieve the flash drive.
Each time I play through I find mistakes or a better way, so this is still a work in progress. This walkthrough is based on Lost Alpha version 1.4007 Developer's Cut (build 7246) with default setup (at installation), played at Master level, and includes recommendations for optional tasks that can be performed during the main storyline tasks.