: The "Dangerous Experiments" update introduced several key features to the base game: New Experimental Weapons (top-tier gear). The Schematics Tree and crafting improvements. Collectible War Figurines .
: FairLight is a prominent "Scene" group that specializes in removing digital rights management (DRM) from games so they can be played for free.
: The file is a "part" of a multi-volume archive (likely a .rar or .7z file). Large game releases are often split into smaller pieces (Part 1, Part 2, etc.) to make downloading and sharing more manageable.