I use the following system to calculate the final score:
In each of the five categories (Story, Art, Sound, Character(s), Enjoyment), a score can get 2, 4, 8 or 10. 2 for something I find truly bad, 4 for something that just isn't good enough, 8 for fairly good and 10 for outstanding.
The sum of the score is divided by 5 and the score is rounded to the nearest integer (More than or equal to .5 rounds it up, less than .5 rounds it down).
STORY (4):
Very, very simple. Some monsters from Chrono Trigger do some stuff. 'twas rather boring.
ART (8):
The designs are, as anyone who has played Chrono Trigger would know, great. The animation was so-so and monsters seemed to differ somewhat from what they should look like.
SOUND (4):
I really don't think the voice actors did a great job. Well, except Gonzales.
CHARACTERS (10):
Outstanding, due to Gonzales being present. AAH, GONZALES! I'M STRONG!
ENJOYMENT (10):
Finally, hearing Gonzales song being sung. Several times. This is the one thing that truly makes this worth watching.
FINAL SCORE:
36 * 0.2 = 7.2, rounded down to 7.
RECOMMENDATION:
If you've played the game, why not? It's short anyway. No point if you haven't played it, though.