Modeling V17: Where can we find "User Interface Construction Toolkit"?

Hello,

We're using Creo Elements/Direct Modeling v17.
I'm learning how to add our own connectors to cabling library.

I found “Creo Elements/Direct Cabling Tutorial 10: Step 1 of 2” says
“CCF-created menus are built via Creo Elements/Direct Modeling's User Interface Construction Toolkit. See the Integration Kit's documentation for more information.”

However I don't know where we can find "User Interface Construction Toolkit".

Do you know where we can find it?

Regards,

Mika