I have been having the same issue. Most of the time, just before the reward section. This cannot possibly be an internet connection issue.If it was, it would happen randomly during the story, not almost always when you are done and the game is about to give you the reward. I even tried several of the suggestions like "pressing the movement keys" while it is doing the cut scene. I was playing with two other players in the same room and a third person in another province and the game would often drop one, two or three people, whether or not one of them was the host. You should be able to rejoin the instance if at least one person is still in it, like you can when you do a dungeon. But just having saved check points would at least something. I was a programmer/analyst for 36 years. The rule is "save your work as often as possible so you won't mind doing it over again if something happens"