Did you just delete your post to repost as a bump?
Your post certainly has no edit tag at the bottom.
Anyway, it looks a lot better now, since it can actually attack with its explosives pretty well.
My only comments are that it gets the disintegrate a little bit early (which is well and good since it's your primary feature), and that there is no specification on the range.
That, and that if disintegrate acts as a line, it's much, much more powerful than a standard disintegrate, since it can effectively hit multiple creatures. Anyway, is the disintegrate explosive affected by SR (I'd assume no), and how is the caster level determined? It's a pretty powerful feature since you could detonate as a standard (to set) plus a free action (to drop it), though I'm not sure if that's what you intended.