Many customers used on Windows XP and Windows Server 2003 machines other names for the OS folder other than "Windows " (eg. WINNT) and now want to continue to use a different directory name for future OSes.
This was possible back then by using the setting TargetPath in the Unattend.txt.
Starting with Windows Vista / Windows Server 2008, this has changed and you can not change the Windows folder anymore. The hard-coded directory where the operating system is now installed is "Windows ".
In the WAIK documentation the "TargetPath" entry is now addressed as “deprecated”:
Windows XP and Windows Server 2003
Windows® 7 and Windows Server® 2008 R2 setting
Platforms Core Team