My apologies for what is undoubtedly a very simple question in advance. I'm actually quite new to the modding scene (big surprise there) and have been experimenting with the Divinity Engine for some time. I've made myself a little map containing several houses, but while I'm able to set up pretty much everything (walls, roofs, furniture, etc.), I haven't been able to discover how to add floors to the houses.
The circular tool for "painting" is useful, but hardly effective when trying to add something constrained by walls. So, my question is: what is the best way to add floors in the Divinity Engine?