10"x11" UTH will be fine. Use the Rainforest pad because desert pads tend to be hotter. Don't place it behind the background you will lose heat and styrofoam emits fumes that can be toxic when heated.

Lights are not necessary, but with the cool ambuent air in your house they will help. Do not use high UVB bulbs and be sure they are not too bright.

Instead of a mister buy a Zoo Med Hygrotherm and hook a fogger up to it. This unit will control the environment according to your settings. A mister may over saturate the substrate which can make your frog ill.