sorry for my english )
I think its more of a character issue rather than the game itself
this is the first time i had played games like PoE (wanted to try it cause i used to watch my brother play NWN)
im currently playing on hard and its quite difficult to micromanage with so many characters to control
have you tried getting durance first?? located on the map next to gilded vale he can actually help you with heals and stuff
i think with 4 characters you can fight shades and shadows pretty easy
and as i play games if i had tried on that area and i kept on dying i try to check if there are other ways to skip the area... maybe it not the dungeon that your supposed to go in yet.