Problem: Koth points can be capped multiple times. I assume this could be done by setting up 'trigger_once' as target entity of the control point, which would then start expanding the bridge? Would that accomplish the task? (steam's currently freaking out, so I couldn't test it, but on paper, it should work...)
If you want to make the bridges move once the point is unlocked, regardless of who's around to trigger it, in the team_control_point entity there's an OnUnlocked output, which should fire once tf_logic_koth's cap unlock value reaches 0
