Try following Tutorial 43 EXACTLY. Once it is working then you can modify and experiment.
title 1 INSTALL Windows 7 32-bit\nThis will install any edition of Windows 32-bit to your hard disk debug off set MYISO=win7.iso dd if=()/firadisk/au.xml of=()/AutoUnattend.xml dd if=()/firadisk/spaces.txt of=()/firadisk/ISONAME.CMD write ()/firadisk/ISONAME.CMD SET MYISO=\\iso\\%MYISO%\r\n map --mem (md)0x800+4 (99) echo Mapping /ISO/%MYISO% as an optical drive... map /ISO/%MYISO% (0xff) map (hd0) (hd1) map (hd1) (hd0) map --hook write (99) [FiraDisk]\nStartOptions=cdrom,vmem=find:/ISO/%MYISO%;\n\0 chainloader (0xff)/BOOTMGR || chainloader (0xff)