I am having the opposite issue referenced in this question. We have users using a custom Kanban board with custom statuses mapped to Iteration Status and they would like the tasks to drive the parent story. Tasks in progress leave the story in defined Kanban status and all completed tasks do NOT move the story to completed status.
I have reviewed the Task State Updates Parent Schedule State | CA Agile Central Help page and I do not have the item enabled and workflow is checked. From what I can tell - the tasks should be driving the story status on the kanban board.
Where else should I look or what is preventing the story status from being updated?