TO BE DONE:

* Crash in PCW16 setup routine. Very odd.

* Kempston mouse. KMOUSE.COM seems to be reading D2 rather than D0 to get the
 X counter.

* Fix the UI font. We need 'tick' and ' ' instead of 'filled bullet' and 
 'hollow bullet'. And the black rectangle is too big.

* On OS X:
	-- xanne: Menu key does not operate, requiring full-screen program
	  to be killed. SDL problem; SDL reports it as 'unknown key' with
	  scancode 110.
	-- Not real Mac OS X programs; no icons, bundles...

* GSX palette funnies on the Windows version; seems to need the GSX palette
 to be set explicitly.

* Builtin debugger.

// What do these ones mean?
// * File chooser: 
//   > Distinguish between DSK and printer file choosers
// 
// * Then get the DSK menu working as it should. 

* Pictures in the menus.

* Add scrollbar to scrolling lists.
* Sort lists of files.
