Hey that's looking pretty shnazzy so far!!!
I tried doing a small battle between nids and space marines over last summer, but It just didn't work out. If you would like a storyboard, I recieved a professionally made one (colour, beautiful drawings) from a guy who was interested on this WH40K forum. I can refer him to you if you would like a very well made storyboard.
ARe you going to have any other unit types? What army will they be facing? If you need help, just let me know. The Skullcrusher mech is about my skill level right now: http://forum.simplymaya.com/showthre...5&pagenumber=2
If you need help with modelling a dreadnought or anything, just pop me a PM and I would be glad to help this short film become a reality.
And one last thing - the pipes and pistons in the middle will look something like this, correct?
I've rigged that mid section for my mech so it rotates on the sphere in the middle and the pistons expand etc.
SO yah, if you need any modelling / rigging help, I can help!
Just a personal question but do you play the tabletop game as well?