I have saved a PDB file of a model generated in Pymol, however when I attempt to import into blender using Bioblender the program freezes after about 5 seconds and stops responding, never completing the import. This occurs both when trying to import a PDB containing a single model, and when trying to import a PDB containing 2 conformations.
It may take some time for BioBlender to upload the PDB file, especially if it is large. During this time, a circle will appear rolling in the Blender window. Is your PDB very big? You may try with a smaller file, to check if it is a problem relative to the way PyMol saved the file. Or just wait for some minutes. After your molecules is imported, do not forget to save your .blend file, so it is ready next time you use it.
Hope this is helps,