scrolling would have to be done in the app displaying the text, xbmc does and im sure others do too. theres really no need for this because the amount of time the bios has control during a normal boot up is to short to scroll much of anything anyway. all it really does is display the text and then not send the set the clear display byte. the welcome screen isnt actually being displayed the entire time the xbox is on, the lcd just isnt being refreshed.