We were doing Shada quest line in Craglorn today... After clearing left wing I got bluescreen on pc(hardware fail which I know about but cant afford to solve it now) but when I returned into game instead of continuing where I left I got teleported out of instance and all quests connected with that instance were reseted to beging. So I had to talk again with that guy inside and he sent me to clear both wings again. Seriously I hope this is just some kind of bug and not how it is normally working.