You know, I've been through the same thing and I know how to fix it finally. You didn't do anything wrong. You know the Properties box, click on the Image bar and where you see "Free Scaling", click "Scale to Frame Size" radio button. If you uncheck "proportional" under this, you won't be able to stretch or resize the image any way you want it. If you keep it checked you will be able to do that. Hope you understand and that this helps.