I would like to second this issue. I've tested this extensively, complete with console commands. I figured that the game was still thinking that it was in a BD cutscene as "You Are Leaving Signal Range" erroneously follows you after closing the third segment.
Video Documentation of the Error can be found here:
You'll also notice that after getting the minimum requirements from the third BD, something about the rewind controls break. I'm betting that's where things collapse now.
Then again, it could also be the transition from the second segment to the third segment that breaks things. I notice that the game would autosave from the transition from the 1st segment to the 2nd segement (as you see in the third link when I go into "Continue" we're immediately at the cow part), but it won't autosave at the Petrochem segment. So maybe that's where it breaks?
Whatever the case may be, "The Hunt" creates a gamebreaking bug here. A real tradgey too as I was getting deeply immersed in that one.
By the by, I tried completing the quest (with Godmode health cheats) and attempted to initiate a new quest to see if that would clear things. No dice. All save functionality dies with the Hunt BDs. Please ensure that whoever is in charge treats this as a priority one bugfix.
Attached is my DX Diag. Tis a shiny (cough to put it lightly) new computer so you damn well know its not the hardware at fault here.