I am following the procedure to post images here. "Insert Image Hyperlink". That's what I did. I don't know why it shows a broken icon. If you right click on the broken icon and choose "Open image in new tab" you'll be able to see it.

I created a 'room' within those 4 walls. It made no difference. Is there another way to create a floor in the basement?

I have played around with the elevations and had no success.