For some reason CreateJS has a default max connections of 1, and modern browsers can handle up to 11. The lesser browsers can handle 6.
So, in your Main.js you could add a line to set the max connections to 6. Here is your existing line (242 of Main.js), with the extra line added:
preload = new createjs.LoadQueue(false,assetspathimg);
That one change could make the page load 6 times faster.