Way too short.
Graphics: All the graphics were nice. Liked the leaves blowing in the wind effect.
Style: Excellent way to introduce your series, although it does, as you say in your comments, leave quite a few questions.
Sound: The music is good. But at the beginning, when it is panning to the soldiers, the sound cuts out rather abruptly.
Very short expecially for the file size. Maybe you should compress the audio more. Hope the next one will explain more about the plot and be much longer.