The "guts" of display rules:
Display Rules are based on every element being evaluated on one or more Conditions.
The Condition Editor allows reading native element types or Item Types and exposing the fields for evaluation.
Here we've defined a condition that is met when a element has a property called State AND its value is equal to "Existing"
If a Condition is met then an Action is performed on the Element:
Symbology overrides can be any combination of these:
Note that displaying different cells or displaying with a different element template is not suppoted.
These means if you want to change cell display, you can't use Display Rules to do it.
If you want a different Action, you need to define another Condition.