How do I 'Zero' the soft limits to the size of my table? Watched the video, but can't see how to set the home to my table size.

Depends what you are meaning by table size, are you actually meaning axis travel?
If axis travel then what you do is, on homing and limits page,  set X and Y min and Z max to zero and then X and Y Max and Z min are set to the travel of their respective axis.
If your home switches are at the positive end of travel on an axis or some other place other than fully negative  you will then need to set a home off value equal to the distance the home switch is away from fully negative.
You can then enable the softlimits on the main screen. Also if you press the display button it will toggle between table view and workpiece view, you may need to Regen after pressing the display button.

Hood

The cut that I can do on my table is X = 0,42"  Y = 0,23". But how do I set 'Home' @ 0,0? Are Am I asking the wrong question? 

Do you have home switches?
Hood

In order to use Softlimits, you have to reference or home the machine in order for the softlimits to know where they are. This is typically done with home switches, but I reference my machine by running it into hard stops and ref'ing it there.