I am aware of this... I have created a portrait and tested (it worked when creating new char). However I am unable to find the folder where all the NPC portraits are located.
Portraits: Create a folder called portraits in your BG2 directory if it doesn't already exist. Every portrait in .bmp format with a maximum file name length of 8 characters in this folder is then accessible via the custom button during character creation and or customising your portrait later in the game.
Only works when creating a new character. You mention customizing portrait later in the game, is this possible without such a tool as shadowkeeper?
Shadowkeeper does have an option to change your character portrait yes. And it's also very possible. But I still need to find the folder to put my custom one in.
Does BGT do something to change portraits folder? If not, I'll just ask over at the shadowkeeper forum. If there is one.