There are few bugs that i've encountered were:
First: fly agaric in lincolnscire (killing bear horde) won't complete aftee i kill all the bears.
Second: mystery in Lincolnscire as well (King of Shitsby), i've interact with the throne, chose any one of the options and killed all the enemies, but the mystery just won't complete, and i have already reload the game, fast travel around and still the same.
Third: The quest "A Fiend out of Hell" cannot proceed any further as there is nothing happened when i interact with those mauled livestock, only when i interact with those people the white colour bar will increases, meaning i just can't go any further from the "investigation" part.
Fourth: After beating the lost drengr in East Anglia region, there is no interact option for me as well.