You guys need more help with the approval process.

[Struggleton!]

Models aren't as simple as black and white "click and button and it renders" - they have variables that cause them to be unpredictable in certain circumstances.
He uses Cinema4D.

I'd also like to add in that renders (if you try to make them look nice), takes more than just rendering it. It requires a lot of manual fine tuning and modifying to make it look nice