I just go in to Otions and then down to Render Scenes Environment, Select Bacground >> Scaled Image and the menu opens, then Edit and next menu open and there i Select the pic i want to use, ok and out of menu's, Draft, Q or A render and i have a background.
V18, V19, V20, V21, 2015/ 16/ 17/ 18 Pro. Platinum
Deluxe V20, V21, 2015/ 16/ 17
Windows 10 Home Premium 64 bit, 32 GB
NVIDIA Geforce GTX 780m, 1 GB