Good to see that you seem to be able to keep to the style of the show, which does have have alot of CGI usage. Its a pity that your using Gmax and unable to render, check that your able to export the models as .OBJ, so any one that use Max or Maya (like myself) can use them if your going to release them. For gaming alot of studios are now using Maya and or switching over to Maya.
I've done some minor UT3 modding and major Source (which I won't do anymore) modding so I will at least be able to get the models into a game