From ReactOS

Requirements

1. ReactOS source code
2. ReactOS Build Environment

Steps

1. Copy boot/bootdata/unattend.inf.sample to boot/bootdata/unattend.inf
2. Open boot/bootdata/bootdata.rbuild
3. Insert the following line: <cdfile base="reactos">unattend.inf</cdfile>
4. Make bootcd

Find TimeZoneIndex here: http://msdn.microsoft.com/en-us/library/ms912053(WinEmbedded.10).aspx

Find LocaleID here: http://msdn.microsoft.com/en-us/goglobal/bb964664.aspx