SRT,
The rendering funtion is a finished product, as you have found out. It doesn't show the cutting process.
Both mill2000 and xp have part drawing rendering and cut part,(with stock) rendering.
The Xp series is slightly different in that you can stop the rendering at every tool change. And XP has a feature called "perfect rendering" that allows you to set different features like light source, shadows,intensity, colors, ect...
Both mill2000 and xp allow you to section your cut part to inspect, very closley, your tool paths and finished part. And both allow you to rotate and zoom and pan, without loosing your rendering.