I still have the same problem. Settings are not getting saved, and the message which I stated in the post above appears.
Try restarting your browser, and deleting the extension and reinstalling it, cause it works I just tried it on my mac OSX and windows with no errors.
For options.html, it works now. But for background.html, there is still some javascript which is on the page in stead of a .js file. This javascript gives the same error for me. I tried restarting and reinstalling, but with no success.