Hmm, this sounds like a more general problem with picking up items that are significant somehow, but it's maybe interesting that I had the same problem with the first item in this quest line. I actually had no issues in the Owlbear cave.

After collecting the 'Necromancy of Thay'/ Powerful Tome book (from the cellar under the Apothecary) and reading, the game can hang on the last line of dialogue and eventually crash to desktop. Saves made immediately before (yes before) or after collecting this book will corrupt in some way and loading will cause a crash to desktop. I could load before the thought-lock/mirror door, but to avoid other bugs with that area I needed to reload all the way back in the apothecary's house.

Last edited by LyellLiar; 11/10/20 04:38 AM.