I'm pretty sure there's no support for Windows Authentication for MDT. While the user who actually executes the litetouch script, they will still always need to log on using some form of credential. You could pre-populate these settings though in the bootstrap.ini
file, however this is a simple text file accessable to anyone who has access to the DS. This is pretty much the only way I know of to automate the credentials page of the deployment wizard.
If you try to start litetouch.vbs without userid/userdomain and userpassword value's, the page will list the username and domain of the currently logged on user, however they will still need to be prompted for their password.
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