This one is fairly hard to describe. I am using -newui parameter. Sometimes, when I try to take an item, it does not work, take command does not do anything. The important part is, both times this happened, I had another item in my hands.

So I try to double-click on an item and this action makes my character put the item in his hands onto his back (an axe, a bow etc.) Following this, if I double-click the unlootable item again, the item goes to my hands and immediately after game crashes with no warnings whatsoever.