[plt-scheme] some GUI questions

Hi,

I'm still not very good at GUI programming with MrEd and the DrScheme 
extension toolkit. I'm trying to implement a "debugging console" for my 
JavaScript language level that instruments the inner workings of the 
compiler and runtime for the curious user. But I'm sort of struggling. 
Here are some of my questions:

- Is it possible to extend the menus of a language level? I see the 
capability-value facility allows me to disable some of the default ones, 
but can I add new ones? I'd like to add a "Display/Hide JavaScript Debug 
Console" item.

- Is it possible to change the fonts of a text% or editor-canvas%?

- What is the proper way to handle the console's state? It should 
ideally persist across multiple executions of a definitions window, but 
there should be a separate console for each tab/window. Where would this 
live? should there be a console field in the tool@ unit, in the 
language<%> class instance, in a parameter...?

If it lives in a parameter, which thread should the parameter be 
attached to? The mzscheme eventspace of on-execute, or the user 
eventspace exposed by the run-in-user-thread argument? I started 
experimenting, but then when I hit "Execute" a second time it caused 
DrScheme to hang, at which point I decided to take a break. :)

Thanks,
Dave