In order to flash the rom you have to have a compact flash card with the rom in it. When it is in there you do a hard reset which is hold record button and press the reset button. It will then flash the rom. Dont do anything while it is flashing for you may kill your Asus. And for backing up your current rom use Asus smartkeeper which also requires a compact flash card. NOTE: If you want to keep all your stuff on you asus then you should use Activesync to keep a backup of your rom, then flash it, then you can reload it i beleive.
Jello
