I experience the same output problems where I use CodeKit because I'm too lazy to reload the page on saving the external javascript file. I get all kinds of errors which I have attached as a screenshot. I don't know if I'm doing something wrong with scoping or using the TweenMax library not as a new constructer as lint tells me that its a bad thing to do but it is kind of annoying. I attached a codepen with the code as being used in order to come to my animation.
http://codepen.io/anon/pen/jbpGJW
