I got a MKS movie encoded with: x264_L4.1
I tried to play it but every single player just crashed... (VLC, Mplayer, Totem, SMPlayer). Then I instaled XBMC and got the movie played but all the colors got messed up (Even for new movies, had to restart XBMC).
I read that XBMC uses Mplayer, by using your script XBMC can use VAAPI too?
I'll test it later tonight anyway.