Some people were having playback problems with the high res version of the trailer, and I've finally replaced it with a newly encoded one. See how that goes. It's a wmv file this time, marginally better in video quality but less than half the size. I've stubbornly kept the 5.1 mix intact, so like the other one it will need Windows Media Player 10 or above to work properly (theoretically).
Incidentally, there's now also a flash version of the low res one.