We can read inside: Unattended Windows Setup Reference for Windows 7.chm: Download http://www.microsoft.com/download/en/details.aspx?id=2458 For your two questions: Yes!
Infinitely value: <LogonCount>9999999</LogonCount> ! Maybe you can try also to give another value for password, because it's the same value for your user account ! Thanks to try it and let us know.