If you are exporting from C4D to obj format, you really need to get Spanki's Riptide plugin. It is free at MAXON's site.... It makes exporting to Poser much easier. 

C4D's obj export is at best "the sh*ts". It reverses the normals and doesn't export all the materials. It will only export the first material. Before he released this plugin the only way to get your object exported with materials was to split the model into groups for each material and when importing into Poser you need to reverse the normals. Riptide takes care of all of these problems.

Ed