Integrated PhysX collision issue

I was trying to use PhysX directly as described here.It looks like PhysX uses cm units like Unreal. I have a ground plane and cube I created in UE4 and a sphere I created directly in PhysX. The sphere and cube fall at the same rate but only the cube collides with the ground. I’m guessing I need to set some flags/settings on the sphere shape.

Looks like it works if I use

physx::PxFilterData collFilterData;
collFilterData.word0 = 1;
collFilterData.word1 = 1;
shape->setSimulationFilterData(collFilterData);

But I might try and use CreateShapeFilterData() instead.