As soon as you load the game or exit CAS, etc all Sims in your game will have preferences intelligently applied (if they don't already have a like and/or dislike in that category). It shouldn't overwrite any existing preferences that are set.
This mod adds a new trait, buff, social interaction, and statistic increases. Primary purpose is to instantly make friends for the purpose of selling them drugs through the Basmental Drugs mod, or having sex partners with the Wicked Whims mod.