Do some 3D Modelling

Hi, am doing a 3d animation movie in which i want a snake character modelled, uv mapped, textured and rigged using maya [login to view URL] am putting a reference file for modelling and one file for the facial rigging also attached to this. one more thing you should give an option like as a sliding button( the button should be like sliding switch which can used for increasing and decreasing the crawl speed when moved from one side to another) which when activated gives the snake its crawling movement automatically (if we move the snake from one position to another and activate the button it should crawl all the way). if any doubts you can ask .