Sorry, I haven't done much work with 3D studio max, only Blender. Explosions are probably done with particle animations. Lowering the gravity settings a touch (usually given as an x or y coordinate) will give you explosions more height, and increasing your random settings will funnel the explosion outwards more. Basically you just screw around with the settings, and do a hell of a lot of rendering as you go. Don't know if that helps much, but try getting a good book, there are several out there that'll tell you everything you want to know.
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August 19, 1942
[This message has been edited by Mosquito (edited February 14, 2002).]