Over half of the problem reports, in Blogger Help Forum: Get Help with an Issue , which mention custom domain URLs, start with improperly setup domains. A handful of the domain setup problems involve improperly chosen registrars - either registrars who can't provide the necessary services, or registrars who won't do their job properly. The vast majority of the setup problems start with bogus DNS addresses. And bogus DNS addresses start with the blog owners.
What Blogger won't tell you