Yea, keep going
1) Your flash is great, so continue on that.
2) Your graphics are good, you might want to tweak it a bit.
3) Keep the story that your thinking of, but add a twist if you can.
4)Um, who should be in it......I dunno, its up to you.
5)Get some nice music in there. Like the Halo music you had in the preview.
Good luck man, and continue with your work. Can't wait to see the full version.