I edit the stock ones, aka I just edited I did not add any. I edited the .tga files, namely: Player_Portrait_Large; Player_Portrait_Button; Player_Portrait_Small; Player_Portrait_Window . However, seing as this particular portrait is from the Distant Stars mod, there was no Player_Portrait_Medium to edit, but this is irrelevant, because my modification does not apear only in the Player Options window, where you select portraits.