I know you have to reset your account. Last time I did it, I had no issues with my eBay account details that I recall.
Have you done the 'Install Complete Version Update'? That has to be first I believe, then the account linking, then a standard update install to pick up your shop categories and seller status, then you should be right. And a backup restore.
If you've done all of those, then I can't think of anything else.