I am having the same problem.
It appears that the original local account/passwords are not working.
Even if you logout, and use the Orion login page, the Domain\Everyone is superseeding the Orion login credentials
We've seen this issue too. It will be addressed in hotfix 2.
I applied the patch from Hotfix 2 released yesterday to no avail. Any other ideas?
We've seen this issue as well - but for us, we had already changed the toolbar option for some accounts to show the ADMIN toolbar so we were able to admin using those accounts.
Additionally, we're able to logout/login using admin account if it's done using a web browser opened locally on the same computer running Orion.
Everest