Moved to the questions forum.
You don't need a library and a library will not help. It is a mistake to use libraries to interact with the layout.
Add this line after you load the layout with the CustomListView:
This will allow you to later find it with:
For Each V As B4XView In P.GetAllViewsRecursive
If V.Tag Is CustomListView Then
Dim clv As CustomListView = v.Tag
End If
Next
Note that with XUI Views the tag is already set for you.