open up the platen organizer and create a new environment based off of an existing one. when you get to the "white underbase" section, choose your %. then save as a new environment. my use of the word "environment" may be incorrect, but hopefully you understand. start from "3 ADULT Black and Dark Hi-Res" and then save as a new file, such as "3 ADULT Black and Dark Hi-Res - 10White", or something like that. but do all of this in the "Platen Organizer".