you are importing a background picture using the File-Import Background feature and then rendering in firefly. This is wrong. (unless you use the P4 renderer). The background will ALways be square and tile. You need to go into the material room, select the background material, and apply your picture as a shader there.

thou and I, my friend, can, in the most flunkey world, make, each of us, one non-flunkey, one hero, if we like: that will be two heroes to begin with. (Carlyle)