Not sure if this is a blight client bug or just a general game bug...
Server: Chaos
Client: 390.25 (using patch to blight)
If I use the create an item button to open the knowledge book to select a form to make, the show product button gets automatically checked. Opening a form and creating something goes ok the first time (slight drop in FPS). Any subsequent create item you do FPS drops from 28 frames from 34 to 6 FPS) and stays there til you close the create window and knowledge book. Even if you open knowledge book using K instead of the icon framerate drops dramatically after that first time using the icon. Once you've used the icon button to craft only way it seems to fix the extreme lag from happening every time you craft (whether use icon or K key) after that is to relog.
If you NEVER use the icon (use the K key instead) to open knowledge book the show product box does NOT get checked and there is no 28 frame drop in FPS.