Dave,
You just add x,y,z values at different points and then tell Copycat what kind of moves you are making and it writes 
the gcode. You can edit the gcode at anytime. Here's an example for the KooL:
1. Click new teach file
2. x & y =0 z=.1 then click rapid move .........G0 X0 Y0 Z.1  START 
3. X=.1 Y=0 Z=.1            "                         G0 X.1 Y0 Z.1 START OF "K" 
4. X=.1 Y=0 Z=0  Z FEED 10 feed move       G1 X.1 Y0 Z0 F10  MOVE Z DOWN
5. click Start Arc       now move to mid point of the arc     click 2nd point
                              now move to end of arc                  click End arc
  Copycat now provides the  code for a G2 or G3 move 
6. Just keep putting in the values for the different points and defining the moves. 
Note that i used G90 / absolute distance mode as i was just "manually" moving to points along the profile and entering 
the values from my X & Y external to Mach DRO. Thus always progressive positive coordinates to deal with.
POINTING DEVICES:
The toothpick was used as a pointer ( cheap and dirty). 
The laser dot could be used as a pointer ( not as accurate as the laser pointer because of dot size generated).
 Probably need around a nice .005" hole in the end of the laser instead of the .010" out of round hole put in AL foil.
 There are a few tricks on it's use that i want to try out which would make finding an odd shaped profile easy.
A scaled cross haired microscope will do the trick, but again need to fool around with what i have.
 I didn't try using the video mode where you could use a camera. Bought a  Radio Shack $20, works, but need to modify it for better resolution and adjustable distance focusing ) which could give .001 accuracy. 
INPUT VALUES:
What would be nice is to have two MPG's set up one for the X & Y and just scroll around to move the axis's.
Couldn't get the jog shuttle to come up, thus the manual movement. Would be nice if the values came from
Mach's DRO's. Need to add that i don't know how or if a  Mach update will affect the Copycat ( ie; lead in rules ). 
BTW, didn't try Mach TEACHING, but it's use may not be the equivilant of what Copycat can do. 
Maybe Ron can give the status of where the wizard is or will go.
What can this be used this for?
1. With a good pointing device you can measure.
2. You could use it to to learn Gcode
3. You could visually create the gcode of a part profile ( reverse engineer it ). 
The above come to mind and surely there are others. 
I need to fool around some and check  the difference in time it takes using Copycat instead other
methods. Think it is quicker! Just another thing to add in our your bag of tricks. 
As usual, a quick and dirty, tutorial would be nice. Maybe the above will surfice.  Maybe when i have some time i will 
do one or you can if you wish.
Copycat is  "KOOL" !  Better than some programs out there that you pay money for.
 
As usual......more than you prabably wanted.........but didn't see anything written about it,
RICH