[ This is where I would ordinarily summarize both opening statements, but it seems that Wintery Knight beat me to it and did so in some depth. Suffice to say that Craig's opening was almost verbatim as his opening in the debate against Antony.]
Kagan does a better job than Antony at demonstrating the possibility of ethics without gods, but he may have seemed more effective primarily because the two men were exchanging interrogatives in a relatively relaxed and informal manner, as opposed to alternately monologuing. Also, it may be that Antony and Kagan fared better than more nontheist debaters because the ground rules called for discussion on fairly narrow topic, which to some degree hobbles Craig's firehose approach of overwhelming his opponent with a half-dozen arguments and then repeatedly calling them out for failing to address each of them in a relatively brief rebuttal period.
That said, Kagan certainly deserves some credit for elucidating the differences between their views in plain language that the audience can follow, and for calling out Craig on certain unsubstantiated presuppositions, such as the fantastically egotistical idea that only ultimate cosmic meaning may make metaethics meaningful.
Overall rating: 4.5 stars