If you are trying to use Release Management or any deployment tool with a network isolated Lab Management setup you will have authentication issues. Your isolated domain is not part of your production domain, so you have to provide credentials. In the past this meant Shadow Accounts or the simple expedient of running a NET USE at the start of your deployment script to provide a login to the drops location.
In Release Management 2013.4 we get a new option to address this issue if you are using DSC based deployment. This is Deploy from a build drop using a shared UNC path. In this model the Release Management server copies the contents of the drops folder to a known share and passes credentials to access it down to the DSC client (you set these as parameters on the server).
This is a I nice formalisation of the tricks we had to pull by hand in the past. And something I had missed when the Update 4 came out