Got it to work today.
It can read and write Sofu files, just like the other libraries.
I made a example JavaScript (no AJAX or server needed) Sofu Editor with TreeView and Value-Editor (so you don’t need to escape your values).
The Value-Editor is active after you click on a value in the TreeView.
You can try it out here (Javascript required, of course)
It works (as I tested it) in Firefox 2.0 and IE 7 (maybe more).
Try this Sofu file (for a little more complex example)
List = ( "1" "2" "3" "4" ) Map = { Content = "This is some demo content" OtherContent = ( { Content = "Some more content" } { Content = "Even more content" } ) <> = "This Value has an empty key" }