Andrew
try this
Create 3D Models from DXF
Use Start Part (inch or Metric), Insert Shared Data, From File, Search and Select DXF file, Open, Import Data As, Protrusion, OK, Extrude, Placement Front, Sketch, Select (Use) from offset tool, Loop, Select an edge, OK, Done, Select extrusion properties wanted, √.
This from my notes! Works in WF 5 should be something similar in CREO. I use it to convert 2D acad to 3D models