3.5a: "Large Deformation" not in Application Mode Properties

I'm trying to follow along with the "Large Deformation Beam" model. I have applied the Structural Mechanics: Plane Stress module. When I go to Physics --> Properties, the Application Mode Properties window does not have a Large Deformation property listed at all. The only properties listed are Default Element Type, Analysis Type, Specify Eigenvalues Using (grayed out), Weak Constraints, and Constraint Type. What can I do to make Large Deformation On/Off appear in this window? I am running COMSOL 3.5a, version 3.5.0.603