The Codebender site has new registration disabled. Their website has a long explanation of how their business model is not sustainable and that they will abandon all users and support by By November (I presume 2016). I find it interesting that a company (Red Bear), which seems to be growing, would recommend that its users use an IDE from a company that is essentially dead. In addition, the latest Arduino IDE, 1.8.2, will not compile sketches. (Even blink fails). The error is "The current selected board needs the core 'arduino:arduino' that is not installed."