Use PhysX Clothing lost something

I want to use PhysX Clothing in some UE Project.I face some problems as followed:
1.I import the fbx,it’s OK.but when I add the .apx file,I lost the things which isn’t cloth.Why?

(.fbx you can see there is one sphere.)
but after use .apx file,you can see the sphere is missed

125554-qq图片20170209184455.png

2.How can I make the apex Clothing things collide the ground or others things like the stairs?

I made a mistake in material import.How can i close this?