My sovereign finds a book that improves combat and it shows up in another unit's inventory who is not in her stack and is very far away.  In fact the unit, I'll call him Clippy the helper guy that you can recruit at the start, found a book that improves spell points one turn earlier.  After the sovereign found her combat book, not only did it show up in Clippy's inventory but his spell book either disappears or is replaced by the one she finds.  

dxdiag

debug

Also, I saved my game right before I had my sovereign attack a spider guardian of the Polapel Mysteics neutral faction, she dies, and the game froze.  Couldn't produce a error report so I included the savegame file.  The sovereign should be saved so that she is next to or near the spider guard if you want to try to reproduce the effect. 

savefile

Thanks