Dear Potrero,
In fact, if you import in Femap a *.PRT NX model with solid & curve geometry entities you will arrive in Femap with solid parts only, not a track of curve entities, the inside Parasolid translator only write solid parts.
You can re-recreate curve geometry in Femap, or alternativelly do the following trick: the DXF import for NX6 DXF models do not runs OK at least in FEMAP V10.02 (I have not tested yet this option in the new Beta Femap v10.1 RC1), then the trick is to export the full NX model as IGES from "File > Export > Iges". Then you go to FEMAP, import the *.PRT, in Femap under GEOMETRY tree take note of the last entity number, then import the *.IGS and then delete the repeated entities. The trick is that IGES format includes all curves you have in NX, but IGES is a very bad format to export solids, then delete the extra geometry created in Femap and you are done.
Alternatively, if you have license of NX Advanced Simulation you can mesh your model in NX AdvSim, import in FEMAP, import geometry as well using the pevious method, and in FEMAP you can associate Geometry & Mesh using "Modify > Associativity > Automatic".
I hope the above helps to solve your problem.
Best regards,
Blas.