I wanted to do USB too, since it's how I've flashed previous phones. I did take a lot of reading in order to figure out how to get the SD card to work. But it comes down to this (I've done this on 5 touch pro's):
- Standard disclaimer - proceed at your own risk.
- Your battery should be above 50% before proceeding.
- Unlock your SPL (if you've already flashed, you're unlocked - so you don't need to do this again unless you re-locked). This is done by running an application that has to be copied to the device (not the SD card) and running it. You can even unlock from the storage card, but I won't go into that here.
- Format your SD card in FAT32. To do this, select Disk Drive on your phone when connecting it and then right click on the removable drive that shows up in Windows Explorer on your machine and click format. Be sure to select FAT32. I have heard of people using large SD cards for flashing, but I'm not sure how. Would love to know
- Re-name RUU_Signed.nbh to RAPHIMG.nbh. Case is important.
- Copy the RAPHIMG.nbh to the root of your sd card.
- Unplug your phone from your computer.
- Hold power and volume down. Continue to hold these buttons.
- Tap the soft reset button with your stylus.
- Continue to hold down power and volume down. If you're fast, you can even wait until after hitting soft reset. But be sure you keep holding down on these buttons.
- You should see the 3-color screen, then the grey screen that says hit power to continue.
- The grey screen will then load the new ROM and eventually say it's complete. Once it says complete, then soft reset with the stylus.
The most important thing is to be formatted in FAT32 and have RAPHIMG.nbh in the root of your storage card.