If you configure an automatic logon on Windows Embedded 8 Standard (e.g. with control UserPasswords) right after the installation you will notice that your configuration gets lost after the reboot. Then you will need to reconfigure the automatic logon again.
The reason for this behavior is that the setup creates the AutoAdminLogonCount value in the registry (HKLM\Software\Microsoft\WindowsNT\Winlogon) which is set to 0 after the first start. If you setup the AutoLogon now it will disappear after a reboot. The solution is to either do an additional reboot first or to delete the entry in the registry.