The floor plan settings are greyed out until you press the buttons for the perimeter and hatch pattern.
You will also need to check you Model View Options to make sure you are not "Over-riding" the zone fill.
If you are these fill options will have no effect.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11