NLTEST has nothing to do with KiX or LOGON.BAT but rather is a diagnostic tool to see what logon servers respond to a request. If %0\..\ allways resolve to the same server then that one server is the only server responding to the request.
That then is not a KiX issue but rather an OS issue.
As for when to use %0\..\, only Wintendos need it so you need to ascertain the OS within the LOGON.BAT and branch accordingly. There are a lot of examples on the board.
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