Save your 3ds or OBJ prop to the Prop Library as a PP2 file. (That will embed the geometry in the PP2 file.) Then bring it out of the Library, place and render. This has worked for me. Sometimes some objects don't even show up in a render. By trying a new camera angle they often will "reappear." There is a way to extract the embedded geometry from a PP2 prop and reroute the reference to a Runtime/Geometry file. Fairly innvolved. If enuf interest, I will knock out a Tutorial (in a coupla weex...)