Allow me to post a TL;DR:
Quick Start GuideName:Age:Gender:Species: Determines base stats, gives Special Skill options
Job class: Adds stat bonuses, gives Special Skill options
Stats: Base stats are determined by species. Use extra Stat Points to increase stats.
Strength (Str): Use for Strength challenges and melee damage. Get +1 HP for every 5 Str.
Dexterity (Dex): Use for Dexterity challenges and ranged damage. Get +1 AP for every 5 Dex.
Mind (Mind): Use for Mind challenges and psychic/"magic" damage. Get +1 IP for every 5 Mind.
Health Points (HP): Health. Hit 0 HP and you're KO'd.
Action Points (AP): Spend to perform "complicated" actions in Battle or Challenges (i.e. hacking, jury-rigged repairs, first aid, etc.)
Imagination Points: Spend on species-specific psychic or "magic" skills (i.e. telepathy, shapeshifting, etc.). Some species don't have this.
Special Skill: A "
Limit Break" that occurs when a Phoenix is rolled during a Battle or a Challenge. Class and species determine your options, and you may switch your Special Skill between Assignments.
Most of the other stuff is either a codex of different options (i.e. species list, Special Skill list, etc.) or else an explanation of the way challenges and battle damage actually work in case you're interested (and/or want to be able to check the GM's calculations in case they screw up).