For those that have not encountered this here is a tip:
At some point you will be given a quest to clear out an area that is suited for settling. You will be tasked to erect a beacon for that area. If you do this task as requested you will be placed in a situation that you must drop everything that you are doing if the area comes under attack. This happened to me, twice. The first time I arrived there to assist the settlers that were there, the second time I didn't see the message until it was too late. But the point on the second one was that I was in the middle of a fight and a long way from the door. I then received a message that I failed because I didn't get there. I still haven't been there.
I discovered another glitch.
When doing battle with some ghouls I lost my pip boy screen and my weapon. I actually had the weapon but not an image of it. I could holster it and draw it repeatedly but not see it. You will see the ammunition count normally. I had to save the game and then do a reload. All came back to normal.
I took a legendary down and I received a set of Power Armor.