No, everything in Forza must be created in the livery editor using the shapes provided.
Adding picture import features would ruin the value of all the artists work, since the place would then be filled with people importing all kinds of images they didn't have any hand in creating.
They should of course improve the art board features in Forza and I'm sad they haven't in Forza 4. I'd like to see more vinyl shapes, more manipulation options, more ways to keep things symmetrical, proper zoom functions and html colour codes.
This would retain the skill level of the artists within Forza, but improve the whole painting experience.
