6 is good for a trailer!
Graphics:
Very nice style of animation! my favorite parts was the backgrounds of the place (Nice crater) and the way the shadow jumped about, the only thing i felt was wrong was the green alien, maybe do a better design for it in the full movie.
Style:
Looks like similar storylines, but in a trailer you can never extract too much for how short the movie.
Sound:
Probably one of the best soundtracks i have heard to a flash movie, reached the right tempo at the right time. Maybe look into mp3 optimising when coming to the final production.
Violence:
No real violence apart from rocks being destroyed, maybe the full movie will have some great fight scenes!
Interactivity: Don't need it, it's a movie!
Humor: N/A
Overall:
As the title says, this i believe is a worthy trailer, hopefully the movie can live up to it's trailer!
Verdict: Nice job!