It has been over a month with no response. This leads me to believe you managed to get your editor working again, so perhaps it was faulty Javascript code on your site, or a conflict with another mod, or another mod was breaking the editor. Also, since that time, Gamma 7 was released (containing some minor editor-related changes), and RC 1 is imminent, which also contains editor-related changes. If the issue persists in RC 1, please open a new report and submit a Support Ticket so we can see the problem in action.
Closing this issue.