Problem with evaluate surface component

shelves rh.3dm (80.9 KB)
shelves gh.gh (19.2 KB)

hi,
im trying to follow the video in the link https://www.youtube.com/watch?v=B8kLEZrX_G0
and i dont understand why the componente “evaluate surface” doesnt work like it works in the video.
i want to extrude the surfaces but cant.
this is how it looks in the video

and this is how it looks for me

will really appreciate any help
thank you

naomiash1999@gmail.com

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