Hey Benign Lump,

  You have received some good answers here which should get you going in the right direction . With regards to Poser models , I would export the model in OBJ format  which is probably the best format for opening in most 3d programs. 
  When modeling in Carrara don't use "creased" edges to create sharp edges , try and create the sharp edges by using very small bevels instead.  Poser 5 had issues with the smoothing angles but I think later versions of Poser you can specify what angle to crease the edges at so it is not as much of a problem.   So, try and make the model look like you want in Carrara without using creased edges and they should export fine to OBJ. 
  Don't give up on creating characters in Carrara's VM room as I have modeled several realistic characters in the vertex modeler . Good luck .