Package pac updated to 1.6.5

Yeah, works better its loading now. But you wrote using codes
library(pac/zdd/vecter-frontier.pl). What does this mean? How do
I run rect(5,5) step by step? The newest version, so that the result

is comparable to this rect(4,4) result:

For example this here doesn’t work, from the SWI pac docu page:

?- [library(pac)].
true.
?- module(pac).
true.
pac:  ?- time(rect_path_count(rect(5,5), C)).
ERROR: Unknown procedure: (:)/2 (DWIM could not correct goal)

And what is written in this thread, works neither:

pac:  ?- use_module(zdd('minato-r2')).
ERROR: source_sink `zdd('minato-r2')' does not exist

So how do I run rect(5,5) step by step after loading pac ?