Hey. I found a Video about the early stage of the devlepoment of the game.
It provides some honest informtaions about the engine, how they are trying to optimize it and even about the sytem requierements.
Remeber this video is from 2012, so some things may changed by now.
Its not my video, I only found it.
Thank you for sharing!
Thank you for sharing!
You gave me the idea to search for others!
This one shows you some different scene that were not in the other videos, like the combat part, where you have to block the right way and then he hit him in the head! Thats awesome!
that scene made it to final game. it’s the water mill under rataje. did they say compost under the toilet? meaning there will be actual manure model? nice. 
Added to OP for better overview 
