I noticed that the link was repaired, but it is still the old version of LazyCAM's graphical user interface. May be I can help some too:
The way to set the material thickness is in the Layers tab at the bottom of the screen. If you click on that tab it will bring up a box. If you've set z=0 when you set up your CNC machine, then material thickness will just be the positive number of the "Cut Start" distance. The "Cut Depth" distance will be how far the cutter goes into the material. LazyCAM isn't like other CAM programs. There isn't a way to setup and show material dimensions. Sometimes I deal with lots of different thicknesses of material. I find in those cases, it is much easier to just set z=0 on the surface of the material using Mach3, and in that case cut depth becomes a negative number and I don't have to get out my calculator.
Next to the cut box is a box for tooling characteristics. If you tell LazyCAM your cutter will only go .02 into a material, but you need to cut .06, LazyCAM will generate three toolpath passes. It all works pretty well, but takes some getting used to. I hope this helps.
Shane Sidebottom