Ok first thing is you can set AutoLimit Override, that will allow you to back off a hit limit switch but be aware that you can jog the wrong way so be careful

Easiest way is to have the home switches for X at the left hand end of the table for X, and for Y at the column, Z is at the top. If you do it this way then setting up Softlimits is easy, you enter zero for X and Y Min and Z Max, then X and Y Max and Z Min is the distance of travel on each axis.
If you have the limits at the other extremes of the axis you still set the Min and Max for each axis the same but you have to enter a Home Off distance for each axis. The reason for this is you want Mach to know that when your tool is at the corner of the table I have marked it is the X and Y zero position.
Hood