Example curses/ncurses Perl widget?

Example curses/ncurses Perl widget?

I am trying to wrap my head around Curses/NCurses (still don't understand
the difference) and perl, more exactly the Curses::UI modules, more
exactly the Curses::UI::Widget package - see
http://search.cpan.org/~mdxi/Curses-UI/lib/Curses/UI/Widget.pm .
For understanding it, I would like to see some super-simple "Hello World"
Curses::UI::Widget to start there.
There is a simple example in Curses::UI::Widget documentation, but that
doesn't work, since it calls $this->generic_focus and it's undefined, and
I have no idea what it should actually do.
Is there some actual tutorial for writing Curses::UI widgets, or at least
some working examples?