Thanks guys, but did anyone even check the code I linked in my message?
I went with 'dump fb0 -> show pretty things -> restore fb0 dump -> refresh screen', which is, IIRC, more or less what GM did (except maybe he used a proper ioctl to refresh the screen, I use eips '' to make sure it works everywhere).
I thought about using screenshot/scrot manually, but I'm not sure it's even there on FW 2/3, so I didn't even try ;p.