[Cataephract]

I have had all the problems you face. Make sure there is no trace of BGII on your pc, except savegames, use add/remove programs and a registry cleaning tool. Then try again. As for the problems with areas not loading, I think it has to do with the .bif file for an area becoming corrupted. Simply go into the cache\data folder, and if you know the particular file for an area, delete that, if not, delete them all. I believe that it then forces the game to reload the areas from disc, and add them back to the cache. Perhaps someone would know better than I. Anyways, this worked for me.