The DMX address tool is a quite easy/self explanatory functionality of QLC+ introduced in version 4.3.2.
It helps you to calculate your fixtures addresses quickly in a visual way.
A representation of a common 10way DIP switch is displayed and you can select the background color, the horizontal and vertical orientation, so that the DIP switch is displayed exactly as you would see it on your fixture.
Note particularly the following, which applies to the 10th switch. Usually, it is used to enable/disable the DMX feature of a fixture, so if your product manual says it has to be raised to enable the DMX control, then remember to do it even if QLC+ displays it set to OFF.