Advancement
Ability Scores
Initially purchased with 15 points.
Characters gain a +1 bonus to an ability every four levels.
Hero Points
Characters start with zero Hero Points. None are gained from going up levels.
Traits
Human characters may start with up to 3 background traits. Non-humans may take a racial trait, plus up to two other traits.
Retraining
Retraining of most things is possible. Some things can be retrained through faction bonuses, which allows you to do it without cost or need of a trainer.
Otherwise, retraining that requires a trainer will require you to find one. Trainers up to third level will probably be generally available.
Time
Under core rules, it takes time to retrain something, a period which is measured in days. This is changed to be weeks. Cost is originally per day, and will now be per week (so the cost does not increase, just the time needed).