@fouxxy

Edit, same issue with unmovable shelf happened in 2 more places. So it is a general problem with this type of interaction. The only solution that worked for all cases was reverting to an older save.

In Grepelgate Fort the shelf that you are supposed to move to be able to jump down the opening below it to get the skill book is stuck. It can't be moved from any side. All destructible objects around it have been destroyed. The character can grab the shelf but not move it at all. I tried reloading the save several times but nothing changed. I am using the latest 1.04 version of the game on PC