Another tip. The guidelines do not say you "MUST" be in AHCI mode. Below is taken directly from the Readme. I'm sure many users will have to update in IDE mode due to chipset / controller issues.
BIOS STORAGE CONFIGURATION
This tool will only function correctly with the BIOS SATA ports
configured to "Legacy" / "Compatibility" mode, or "AHCI" mode.
Some BIOS configurations support SATA port modes such as "IRRT",
"RAID", and "Native + IDE" mode, which are not supported by this
I have a ASUS P5B in AHCI, when tried to upgrade the FW it did not found the drive.
I disabled the JMICRON onboard controller (in bios), keep the ICH8R in AHCI and this time the FW upgrade software found the drive.
After that the upgrade went well.