Trench Run states:
"You may engage the Death Star dial as though it were a dark side objective (it is not an objective)."
Since it is not an objective, it seems that the only way to damage the Death Star dial with Trench Run is through engagements. Cards such as Rebel Assault (which can damage objectives) cannot be used on it. Is this correct? If so, it's a little disappointing that the cards in the objective set don't synergize very well with Trench Run.
Also, what about Target of Opportunity? That says "deal 1 damage to the engaged objective"? Is the Death Star dial temporarily considered an objective during an engagement? Or do you ignore that effect too?