Well, this looks very strange. I always have all mods you listed except sell scrolls and _TWMdemo_3.52R3_BG1. I glad you have resolved all issues, but there is clarification question.
Did you start looking for Cearwin after found dead messenger with note? Cearwing won't appear at Nashkel Carnival until you find killed messenger and get his posessions. And you must complete Cloakwood mines quest before you encounter messenger. This is proper quest start.
Actually I think your further problems may lay in this if quest didn't start properly. I played BigWorld several times (at least BG1 part) and never encountered problems with TSoA quests.