This is discussion archived from a time before the current discussion method was installed.
Also used the awkward and extremely math-heavy 1980s incarnation of Traveller as the rule system.
Quite possibly the single most depressing RPG setting ever created.
Darktalon: Twilight 2000 version 2 used the rule system from Traveller: The New Era, which was from the 1990s and not especially maths-heavy. The original used its own system, unrelated to any version of Traveller, which did have more maths and could get awkward. It's indeed depressing, but a realistic post-nuclear-war setting is doing something wrong if it's not.