Just wanted to make it known that I do believe that the making the Shadow Dragon Scale armor (obtained from Rasaad's TOB quest) seems to bug out Cespenar. If you make this armor, Cespenar will not talk to you anymore, clicking on him will not bring up his usual list of dialogue involving a list of items that he can make for you. I had to reload to a previous save and ignore the option to make the armor, which isn't a big deal as I really don't have anyone in my party that can use it. However, this can be a pretty big deal for those who do use it. Just wanted to make it known, thanks!