[x-net]

Так делал, вот приведу пример winnt.sif

[Data]
AutomaticUpdates="No"
Autopartition=0
MsDosInitiated=0
UnattendedInstall="No"

[Unattended]
UnattendMode=DefaultHide
UnattendSwitch="No"
OemPreinstall="Yes"
OemSkipEula="Yes"
FileSystem=*
WaitForReboot="No"
DriverSigningPolicy=Ignore
NonDriverSigningPolicy=Ignore

[GuiRunOnce]
"%WinDir%\System32\hidcon.exe run.cmd"

[Identification]
JoinWorkgroup=WORKGROUP

[UserData]
ProductKey=""

[Networking]
InstallDefaultComponents="Yes"

[Shell]
CustomDefaultThemeFile="%Systemroot%\Resources\Themes\WinXP.Theme"