I think both this thread and Game becomes unresponsive - Gnarled Door
are talking about the exact same issue you're describing, where the game has to transition a dialogue scene into another location for the scene through a black fade in transition
, but the black fade in transition does not progress into the next scene. So you still have your UI and buttons and can hear everything, but cannot do anything.
I also experienced this issue myself, however only once and never am able to get it cooked into my save file, as quitting the game and reloading fixes it for me.