Your guide has way too many steps you don't have to do in order to flash a benq.
1. you dont have to make a usb boot drive with the hp tool, just use iprep.
2. no need to get the number of your drive with msinfo, dosflash does it for you, tells you how in the readme file in dos.
Here is the easy way to do it.
1. make boot drive with iprep, put dosflash16 on it, put the benq i-extreme , whatever speed you want to use folder on it
2. reboot with the usb drive, dont disable your sata drives, make sure your benq drive is powered off.
3. after booting turn on the benq drive
4. type dosflash, hit yes, it tells you what to do next, mainly power off and power on the dvd drive
5. select your option that dosflash presents, read write erase.
6. then just run the bat file inside the i-ixtreme directory to create your hacked firmware, repeat the dosflash instructions above to write.
All those extra steps in the manual are a waste. Also the readme file in dosflash pretty much describes the above method..