In general the registration process behaves like a wizard. I can go back to the first screen, however if I try to go back on the OpenId page I am receive an error about my account is in use.

The wizard did not indicate that my account had been created yet. So I expected I could still change information. It may be a lot more user friendly to create a summary confirmation page at the end where the user can confirm what is about to happen and have a clear step where the account is actually created.

Once the account is created the user should be able to go back where the receive errors.