"Requires" Numenor's Unleveled Wall - really?

[fytj]

I have a question about Numenor's Unlevel Wall hack/thing/whatever. As you might know it is said to be somewhat unstable so since I'm not a builder I decided not to install it. But sometimes when I download lots I see that it says that unlevel walls is required. I'm just wondering why it would be since I'm not going to build/change the lot. Could it be that the lot still works as long as I don't do anything build mode related? And what happens if I try to install and load a lot that is said to "require" it without actually having installed it? Will my computer explode? I'm a bit afraid of finding out myself so I thought I could ask here, see if someone knows more about it.

[ancienthighway]

Many of the parameters listed in section 2 only affects the building phase, and are not used by the game to display the lot.
For instance, if you edit the "MayAttachObjects" and the "MayChangeSurface" in order to apply some sconces and a wallpaper to a basement wall, who downloads your lot will see the sconces and the wallpaper even with the original Maxis walls.txt.
Obviously, this method works only if you edit a wall already existing in the walls.txt: if you create a brand new wall, with its own custom wall number, downloaders need to edit the custom wall accordingly!

(italics mine- quote from THE "PARTITIONS": WALLS, FENCES, FENCE ARCHES)
The Unlevel wall has a custom wall number and need to be in the wall.txt file for it to appear correctly.