Found this at http://homeserversho…1-from-usb.html

“Caveat: as with any 64 bit Windows OS install to USB drive using this tool, it will give you an error in the fourth phase (making the drive bootable) if you try to run it from a 32 bit system. This is because it can not use/understand the 64 bit bootsect.exe file from the iso.

Easy fix is to extract the bootsect.exe file from a 32 bit Windows ISO and paste the file into the Wibdows 7 USB Download Tool program folder. It will then use the 32 bit version which works just fine to boot the 64 bit OS install.”

Well you can teach an old dog (like me) new tricks.
Or at least remind me of them….