I downloaded the latest build updated on 4th Dec 2012 Cocos2d-html5-v2.1, I was trying this (http://www.gamefromscratch.com/post/2012/06/06/Cocos2D-HTML5-tutorial-2-Why-it%E2%80%99s-Hello-World-of-course.aspx) tutorial but I am getting the following error in the console window of google Chrome Uncaught TypeError: Cannot read property ‘loadExtension’ of undefined on platform/jsloader.js line 114. I double checked the 4 files coded in the link. what i am doing wrong and everything seems ok but then ????
The tutorials on GameFromScratch uses Cocos2d-html5 V2.0.
So, if you want to upgrade game engine to V2.1, please refer to this wiki [[Upgrade Guide from Cocos2d-html5 v2.0 to v2.1]].