Z travel height should be higher than your part.
Z Probe depth is how deep you want to go. I think setting it to 0 would be the bottom of your part.
Stepover is the spacing of the point grid.
Feedrate is how fast to probe. Don't probe too fast, or the probe won't be able to stop when it's tripped. It has to decelerate after it makes contact.
Do a test probe in air and make sure the switch stops every time it makes contact.