Update. Although I have not resolved the issue with the rudder I have learned a few things I wanted to pass along. I have found that blender files will import into phoenix builder if you check the box "write Normals" in the obj export options. Also, obj files exported from Wings 3d will also import into builder. Both of these programs are free. I must add that having imported the files into Phoenix Builder, I have not finished the process and tested models imported this way in the actual simulator.

Jerry