Floor reference lines are typically red but you can quickly to change them to be any color you choose using Chief Architect.
Changing the layer for multiple objects within a Chief Architect plan can be accomplished very quickly using this method.
Here's how to show or hide the wall layers in your Chief Architect plan.
You can control the display of objects by checking or unchecking the Display column in Layer Display options for the active view's layerset.
The layer sets dialog box can be a true productivity enhancer once you really understand how to use it.