If for each box, you could somehow select all of the scripts and styles inside, and allow them to be edited, with the edits being visible to all in the app, then this tool would not only be great for quick discussions about design, but also a way to quickly agree on it's solution. Don't forget being able to somehow copy that code somewhere for when you actually make the change!
A screenshot of the change with the dialog could also allow freelancers to keep a record of approval with evidence!
While this may be a lot of work, the benefits could mean this app being used extensively in the design and UI process. Let me know if there's something similar integrated.
EDIT: This type of functionality is something that I would pay at up to 50 a month to have because it would save time opening an editor, making the change, reviewing the change, and finally committing the change when all I want to do is get approval from a client.
Look to the stars with this, it's a brilliant tool, and has many possibilities. Good luck!
My only advice is to keep some form of this service free.