The Maya Mountain is correct
To get quick shadows out of Maya for this shot, you can import your background image as a background in Maya, place a plane under your model that is lined-up with the ground plane,
add a "use background" shader to the plane, and when you render, you will get shadows on the "ground"
Another idea is to run a shadow render layer pass.
Good luck!
Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS
izzylong.com