Had many problems for hours trying to install this into userbot. I'm very new to SFM. So I did not quite understand the description maybe but

Here's what worked for me after hours of trying to solve it:

1st step: DOWNLOAD THIS FROM THE DRIVE LINK IN THE DESCRIPTION.
2- Then you go to the steam and right click SFM and browse local files.
3-Go to the game folder, create a folder name it whatever
4-Unzip the contents, it says materials and models. Do not extract further, just paste these into the folder you just created.

Nothing else.
It may look invisible in the preview section in SFM but when you load the model it will show up.
Took me hours to solve it
Console kept saying
Binding uncached material "potterywheelpanelwireframe", artificially incrementing refcount
MDLCache: Failed load of .VVD data for "model name"
hope this helps