[Asus  Eee Pad Transformer Prime] flumpster:
Below is what I did to generate nvflash backups on Hairybean 2.31 without losing your OS or downgrading. Do not follow these instructions if you are not on Hairybean 2.31.

You must have adb drivers and apx drivers which can be found here http://xdaforums.com/showthread.php?t=1426502.

If the adb drivers do not work for you from that download then use these ones. http://www.androidfilehost.com/?fid=22962010882834442

Instructions

Create a folder on your hard drive called nvflash (e.g. D:/nvflash)

Download the following 3 files and place them all in the folder. nvflash-tools-win32.zip , flatline_tf300.img and adb-fastboot.zip.

Extract nvflash-tools-win32.zip and adb-fastboot.zip inside the folder.

Hold down shift and right click on folder and select "Open command window here"

Boot prime into fastboot by either selecting it from shutdown menu or by holding volume down and power when switched off.

Type the following into command prompt.

fastboot-windows.exe -i 0x0B05 flash recovery flatline_tf300.img

This will flash the new recovery needed for the next part. Once that is complete type the following to restart the prime back into OS.

fastboot-windows.exe -i 0x0B05 reboot

Once restarted go to the shutdown menu and select reboot to recovery. You will end up in a custom Clockwork mod recovery. Use volume keys to move and power button to select.

Go into the "Advanced" menu and select the "Wheelie" menu.

Now you need to select the "Step 1: Flash AndroidRoot BL". When it has finished the Prime will power off.

Press the power button to reboot and let the blue line fill all the way. When it has finished it will reboot into OS.

Once restarted go to the shutdown menu and select reboot to recovery again.

Go into the "Advanced" menu and select the "Wheelie" menu.

Now you need to select the "Step 2: Generate wheelie blobs"

This will now create your wheelie blobs onto the prime. The wifi upload did not work for me.

Once it has finished go to the command window you have open on pc and type the following.

adb pull /data/media/AndroidRoot

This will pull your wheelie blobs from the Prime into the folder you created earlier.

Once you have them files hold down Volume UP and Power button for 10 seconds until the Prime restarts and keep holding them for a few seconds longer. The screen should stay blank and you should be in APX mode.

Make sure you have the APX drivers installed by checking your device manager for any conflicts.

Now type the following into the command window.

wheelie --blob blob.bin

This will place you into NVflash mode and you then run the following commands.

nvflash --resume --rawdeviceread 0 2944 bricksafe.img
nvflash --resume --read 14 factory-config.img
nvflash --resume --read 7 unlock-token.img

These will create the last of your backups needed in the folder you created earlier. You need to back this folder up in triplicate as it is your lifeline if anything goes wrong in the future.

Once it has all finished you can now hold the power button down on your prime for 10 seconds and let it boot back into OS.

You now have all your backups in that one folder and to finish up I would advise going back into the custom recovery and reflash the "Upgrade Hairybean 2.31 (4.2.1) Bootloader & TWRP (2.5).zip" which will give you back your TWRP and newest bootloader.

I am not supplying support on this so please don't ask me anymore than is above. I know it works and just thought you would all want to know.