SOLUTION - boot multiple boot.wim files from a single USB flash!
Here is grub4dos entry to modify file bootmgr to boot using \boot\bc1 instead of \boot\bcd
must use Vista RTM SP0 version of bootmg (note: the write command permanently patches the file bootmgr)
title WinPe BCD (boots using /sources/boot.wim)
write --offset=0xE28 /bootmgr \xEB\x03
write --offset=0x54B6c /bootmgr \x44
chainloader /bootmgr
title WinPe BC1 (boots using /sources/boot1.wim)
write --offset=0xE28 /bootmgr \xEB\x03
write --offset=0x54B6c /bootmgr \x31
chainloader /bootmgr
To make BCD or BC1 you run a script as follows (example for BC1):
copy \boot\bcd \boot\bc1
bcdedit /store \boot\bc1 /set {bootmgr} nointegritychecks YES
bcdedit /store \boot\bc1 /create {ramdiskoptions} /d "Ramdisk options"
bcdedit /store \boot\bc1 /set {ramdiskoptions} ramdisksdidevice boot
bcdedit /store \boot\bc1 /set {ramdiskoptions} ramdisksdipath \Boot\boot.sdi
bcdedit /store \boot\bc1 /set {default} device ramdisk=[boot]\sources\boot1.wim,{ramdiskoptions}
bcdedit /store \boot\bc1 /set {default} osdevice ramdisk=[boot]\sources\boot1.wim,{ramdiskoptions}
If you want to boot using /sources/boot2.wim and /boot/bc2 then change \x31 to \x32 and bc1 to bc2 and boot1.wim to boot2.wim
Now you can have many boot.wim files (pev2/3) on the same USB stick and boot from a grub4dos menu! just name them boot.wim, boot1.wim, boot2.wim, etc.
You could also rename files, so for instance, you could have a Vista install DVD and a Win7 install DVD on the same USB flash drive by having two boot.wim files, and renaming say vistaUlt.wim to install.wim file before running the boot.wim for the Vista Ultimate boot.wim??,
Anyone know how to rename files in grub4dos???
I used RMPrepUSB (of course
) and the Install Grub Bootlaoder button to install grldr.