All you have to do to add a new level or change the name of a level is go to the bottom of the page and click on the level word.
This will bring up this box:
Click the Add Level button at the side of the page and a new row will appear below.
You can then name and set the height of your new floor to be whatever you want it to be.
To change the name of a level just double click on the name of whichever level you wish to change and it will give you the ability to type a new name for that level.
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