Bryce can only export two types of objects: Terrains/symmetrical lattices, and imported mesh models. Cubes, cones, spheres, etc. cannot be exported. To export a terrain: go to the Terrain Editor and click the Export button (right below the 2D grayscale window). To re-export a previously imported mesh, choose Edit Mesh (or the [E] button), and then hit Control-D. In general, bring your Poser figures into Bryce for rendering in-scene, not the other way around. This also requires a bit of work: details can be found in the Tutorials section on the sidebar ----->. You can also render a complete Bryce scene and then use it as a 'backdrop' image in Poser, although your poser figure will not interact with any objects in the Bryce scene (won't cast shadows, etc)