[plt-scheme] Help writing non-trivial applications.

Is there a book on using PLT-Scheme to write complex interactive 
applications?

Is PLT-Scheme source code to a complex application(s) available, such 
as a usable web browser, word processor, etc?

What is the best way for someone to learn to master the GUI aspects of 
PLT-Scheme?

Obviously example code is helpful, and the 'cookbook' stuff is great.  
But there seems to be a big gap between the excellent technical 
documentation and the kind of incremental tutorial that engenders 
understanding and mastery.

On a personal level, I'm very confident about using Scheme for 
traditional academic exercises.  What I'm not too confident about are 
the event-handing idioms, styles and 'best practices' that can mean the 
difference between successful project architecture, and a functional 
nightmare.

Thanks for any advice and ideas, in advance.

- DR