Conversion from CATIA to Siemens NX is not supported yet :(

CATIA is a multi-platform software kit for CAD/CAM/CAE, PLM and 3D, created by the French company Dassault Systèmes.

Commonly referred to as a 3D PLM software suite, CATIA supports all stages of product development, including conceptualization, design, engineering and manufacturing. CATIA facilitates collaborative engineering across disciplines around its 3DEXPERIENCE platform, including surfacing & shape design, electrical, fluid and electronic systems design, mechanical engineering and systems engineering. CATIA facilitates the design of electronic, electrical, and distributed systems such as fluid and HVAC systems, all the way to the production of documentation for manufacturing.

NX, also known as Unigraphics is an advanced CAD, CAM, CAE application which is owned by Siemens PLM Software. It is commonly used for design, engineering analysis and manufacturing. NX is built on Parasolid and runs on Linux, Microsoft Windows, and MacOS.

On the CAD level UX provides parametric solid modeling, freeform surface modeling, reverse engineering, styling, engineering drawing, PMI, reporting and analysis, knowledge-based engineering, sheet metal design, assembly modeling, routing for wiring and piping. In CAE key functions are stress analysis, kinematics processes, CFD and thermal analysis. As for the CAM level, the main function is numeric control programming.