Written in C++, HeeksCNC is an add-on for HeeksCAD http://code.google.com/p/heekscad/. The user can add machining operations. These can then be output to NC code. The NC code is then shown as red and green lines on the screen. The NC code is generated using Python script, so it can be configured for different machines.

See some example of HeeksCNC being used here: http://code.google.com/p/heekscnc/wiki/CaseStudies

HeeksCNC uses pycam for the "Zig Zag" operation HeeksCNC uses libarea for the "Pocket" operation HeeksCNC uses libactp for the "Adaptive Roughing" operation

There is a Windows installation on the downloads page of this web-site, which installs everything you need, including HeeksCAD and Python 2.5

There are OpenSUSE rpm files here http://software.opensuse.org/search?baseproject=ALL&p=1&q=HeeksCNC

You can usually find me (DanHeeks) at the #cam IRC channel on FreeNode

Instuctions on using HeeksCNC are here: http://code.google.com/p/heekscnc/wiki/HowToUse