I'm most interested in hearing more about chargen. What does Cortex+/Prime do differently at that level to make characters distinct? What does character progression look like?
The process of generating characters depends on a particulars of a setting:
1. Establish list of trait sets applicable to characters in your setting. For example, if I were to run an investigative horror campaign Call of Cortex, I could pick the following:
attributes: Physical, Mental, Social, Otherness (Otherness is a measure of psychological stability and one's ability to relate to alien agendas: 0 means you've got nerves of steel, and alien influences cannot affect you, at d12 you are one step from becoming a part of a problem)
skills: (let's use the list from the rules)
distinctions: (four in-character statements that describe character's specialties, use Plot Points to activate benefits)
relationships and assets: (important people, important organizations, important resources - some of these relations may be antagonistic)
2. A character has "milestones" or "sessions".
2.1 "Sessions" - complete a session, record its name, then spend a session or sessions to improve a character.
2.2 "Milestones" is a list of thematically grouped actions and goals that give you XP. For example, a doctor in Call of Cortex could have the following:
1 XP: successfully diagnosing and treating a patient
3 XP: making a discovery that defies your medical knowledge
10 XP: encountering, researching and making use of otherness
2.3 In general, you need to survive three sessions to step up (improve by one step) an important character feature.