[plt-scheme] Multi-column listbox?

Hi,

At the risk of repeating myself over the years, has anyone managed to  
get a multi-column listbox with platform native look-and-feel working  
in MrEd?

I've tried to make one a long time ago based on editor%, but gave up  
when it became clear that it would never look similar enough to what  
users are used to (like Aqua look-and-feel on OS X).

This is really the only missing feature by now that keeps me from  
using MrEd for GUI applications. (TCL/Tk bindings are too fragile and  
require too much installation on the end-user machine.)

Best regards,

Erich