Because your total was higher than his, his attack is unsuccessful. Unfortunately, this doesn't help you much if its a PC vs. PC combat. Hopefully this oversight will be corrected in the full rules. Once again, I'm impressed. In order to case a spell a mage must know the spell and have it written in their spell book.
Magical spells have difficulty numbers.
The complex the spell the higher the difficulty number, the higher the difficulty number the more turns it will take before the mage is successful. Now that's a nice system all by itself, then they add a couple of extra touches which give it the potential of being an excellent magic system. He can either let the magic fail or take 3 points of Stun damage in order to hold the magic under control. If he ever rolls two 1's in the same roll, the spell-casting automatically fails and the mage takes stun damage equal to the remaining number of points required to complete the spell. The adventure picks up where the short story left off, with the players picking up pregenerated characters who were introduced in the story.