I don't own a davinci of any kind, but from what I understand, each printer is unique. Because your nozzle can sit slightly higher or lower, your sensor can sit slightly higher or lower, and your bed can also sit slightly higher or lower. It is all part of the calibrating and measuring process of getting set up.
In your guide, is there a part that explains how to do it step by step?
For mine, after testing the sensors, you lower the bed until it is below the sensor. Home Z, and then adjust by mm and .mm until the nozzle is a paper width away from the bed. Whatever that number is, is the value I have to enter.
RoVa3D with five nozzles (first nozzle down, four to go)
Slic3r and Pronterface
Filastruder and Filawinder - soon enough
Current hurdles - humidity, offsets