Well, Aggregator is an active transformation. if you are making a new port in aggregator, you wont be able to surpass this transformation for other ports while going to update strategy.
Without asking you for more of your functionality, you can fix this by simply flowing your ports through aggregator. Whatever you need in update strategy, make sure they flow through aggregator... Src Qualifier -> Aggregator -> Update Strategy.
I hope its clear enough, if not, think about going through documentation about active transformations..