Well Mr. Hall, I didn't mess with defaults. I've been doing this for awhile and it is not something I thought to check. Your answer helped, but your rudeness did not.
I was thinking maybe there is something interfering, so i deleted the roof planes and reduced the door size on one wall. However the icon still does not show.
When You click on a roof plane you can choose to show it on the floor above, unless you want it to show up on the floor below. It is a button in the bottom edits. No reason to create a new floor, I don't think.
Hi,
You can customize your foundation of your garage by selecting the wall and changing the preferences of the wall. You can also change preferences when you build the foundation for the room. Once you make the stem wall you can make an elevation and break the wall at each place you need it and stretch the wall up.