Yes it imports jpg and gifs and maybe others, I've only used jpg and gifs. Open fabric library and click import. Find your file where you saved your images and highlight all of them at once and click open. Then put save to sketchbook. The fabrics will be in the library. You can select a fabric and see how it will look in a stack and whack using the symmetry tool. I just discovered this feature and it is too much fun.
Some good how to videos on doyoueq.com