[racket] Racket GUI and Sound Infelicities

I've been very pleased with Racket as a programming language, and I quite like the DrRacket environment (especially its debuggers). However, there are some serious problems with I/O. It's more difficult to repair these from a 'user' (programmer) standpoint than other problems, because fixing

[racket] drag-and-drop in a Windows-Explorer-like GUI

I've been trying to figure out how you would write something with a GUI like Windows Explorer. It looks like it's possible to drag-and-drop in a icon-view (though you would have to write the icon-view widget), but there would be no way to drop onto directories in the tree-view (hierarchal-li