Well done for sticking with it despite the frustrations!! Small mistakes seem to loom large in a quilters mind, and often they are not noticeable to anyone else. I'm sure it will be beautiful, and your DIL will love it. I've had the same problems with patterns in the past, as have others that I know, and I think there ought to be a Nobel prize for patience, and that quilters ought to win it!! Anyway, chalk it up to experience, and feel proud that you completed a very difficult project.