The adbots are worse on this forum than any other I visit.
Anyway, I've only played DKS, but my understanding is that most of the generators were removed in the transition from ED+FoV to DKS, as were most of the barriers inside the fortresses. In Stone's Fortress, for example, there's only one, and I don't think there are any in the rest of the fortresses.
For the one in Stone's Fortress, you have to get on the island that's protected by the barrier, which you can do by either flying above it and dropping onto it by switching to human form or finding a teleporter somewhere in the fortress that will bring you near to it. As for destroying it, I don't think that it's labelled, but it should be pretty obvious what it is based on a dialogue that occurs nearby and the fact that it's the only thing in an otherwise featureless area. Just use your weapon on it - or stand near it while an enemy attacks with his bow and dodge the arrow, which is how I accidentally destroyed it during a mini-boss fight.
