In Blender 2.8 the NURBS objects do not appear at all in a render. Default Sculpting sphere in Blender does not render in ProRender 2.0, nor any sculpted objets created from the sphere, regardless of shading.
To Reproduce: Create scene with mesh sphere, mesh cube and NURBS sphere.
Set all 3 objects to same material. Evee and Cycles renders show all 3 objects.
ProRender rendering does not show the NURBS sphere at all, but other 2 render normally.
NURBS appear to work just fine in Blender 2.79b and ProRender 1.8.
iMac 2017 64GbRAM Radeon Pro 580 8Gb.