You should always use the latest version when you are tracking bugs. At the moment : 1.1.29. My NWN2 installation works very well. I would recommend that you install the game in a clean prefix, without modifying anything. If necessary, use winetricks to add the implementations you need. Pay attention also to : http://appdb.winehq.org/objectManager.php?sClass=version&iId=17426
