on my 3.10oe-a i replaced the jap and chinese fonts with the normal font (copy,paste, rename) to give me 2.5mb of space goto recovery enable flash0 to usb and copy what ever gameboot to \vsh\resource\gameboot.pmf
p.s. you can use any size gameboot but after a second it cuts of so your wasting space, i used an xbox360 gameboot (1.6mb) and it show half the movie clip then boots the game, it works just fine but doesn't use it all so it is a waste but it looks excellent

at the mo ive got the matrix gameboot installed which is cool looking.