No Errata
Q: If a fighter is taken out of action by Trap, does that happen before or after they are driven back?
A: After.
Q: If a fighter is driven back by an Attack action that was not successful, and then Trap is played to deal damage to that fighter, is the Attack action considered to be successful?
A: No. The damage is dealt by the ploy, not the Attack action.
Q: I make an Attack action with my fighter, and after the dice are rolled it is determined that the Attack action is successful and will cause damage. My opponent plays Rebound as a reaction, but fails the roll so nothing happens. We continue to resolve the Attack action: my fighter deals the damage, and I choose to drive the target fighter back. Can I now play the Trap reaction?
A: Yes. The trigger for Trap is after the fighter is driven back, which is a different trigger to when the Attack action is determined to be successful or not.
Q: Can Trap and Pit Trap be triggered by the same Attack action?
A: Yes. Trap is a reaction that happens during an Attack action, and Pit Trap is a reaction that happens after an Attack action.
Q: When a fighter is driven back into a lethal hex, do they suffer the damage from the lethal hex before I can play Trap?
A: Yes.