I use Dosflash32 1.6 to flash my BenQ. It's a windows-based app, and it sends the correct "Magic" strings to the benq drive to make it writable. I *think* you have to have a VIA6421 SATA card/interface for it to work though, but I'm not sure. I don't even use iPrep anymore.
Here's how I do it:
While in windows, connect the SATA cable to the BenQ drive and power it up. Nothing will happen initially.
Open DosFlash32, after a few seconds a popup will appear that says "MTK vendor info failed on port xxxx". Click NO until you see a message that says "BenQ VAD6038 was detected on port xxxx (remember this port), do you want to send the magic keys etc" then click YES and choose the port it said from the pull down list. Make sure the TYPE is "Serial with Status 0x73" and you're ready to flash the BenQ!
This post has been edited by ghaladream: Today, 12:50 AM