There is no second debugger. The Swat stub that runs on the target
machines is a DOS program written in C (with maybe a touch of asm).
Anyways, I've answered this same post in detail already on both
comp.lang.tcl and on comp.os.geos. If anybody wants the gory details let
me know. The basic answer is that there is no port of Tcl and/or Tk to
GEOS. Period. For various reasons it wouldn't be worth doing (though of
course that's arguable :-).
Happy holidays,
John