The "complete piece" of this mod typically refers to the full suite of modules that adjust various life stages:
The mod is designed to differentiate how different age groups—specifically Children, Teens, and Elders—interact and behave, moving away from the "one-size-fits-all" social animations in the vanilla game. BG - Ages Behaviour Tweak
You can find the latest versions and detailed documentation for each "piece" of the mod on Zero's Patreon or via community discovery platforms like Pinterest and Tumblr . The "complete piece" of this mod typically refers