Meh.
I tend to agree with many of the others--very childish and sometimes just unfunny humor. The first one with the Wraithlord was the only one that I even slightly chuckled at. Not a complete bust, because some of the animation was quite decent, but it fell flat on its power-armored ass when it comes to humor. If you do a sequel, I'd suggest some slightly more mature jokes that fit with the universe a little more. The excessive grimness of 40k is what makes it what it is, so try to fit with that theme a little more next time.