All floors can be edited to any shape you desire. To edit a floor's form, click on the edit tool under the "Form" topic. Dots will appear across your building, marking the editable points with blue dots and potential points for creating new segments with grey dots. Delete the wall segments by double clicking on the blue dots. Drag the blue points to adjust the position of a corner, or click on a wall segment and drag it by the arrow to move the entire wall evenly.