So will we not be able to import custom pics into the game like as in S2 through mods,
I dont understand what exactly you are trying to say.
Well, in TS2, you could paint custom pictures in the base game and early expansions by swapping the screenshot file before the sim started painting it after painting a still life. Later on, the facility to directly paint those paintings was added.
In TS3, you simply can't, you can only paint the premade paintings in the game.
