Are you using the theme version Daniel provided in response #21094?
After that I’m not too sure (if you got one previous in the thread it may not be the most recent one which was doing the thing you mentioned above. Would try deleting the theme folder all together and reuploading the one from 21094 then try the save button. It should hopefully allow you to add the sidebars then you’ll have to repeat the process for adding the sidebars. Note that the save button doesn’t actually save any of the position settings found below the add sidebar area.