Conversion from Unigraphics to CATIA is not supported yet :(

Unigraphics is a former name for Siemens NX, an advanced CAD/CAM/CAE software application suite. However, veterans are still using the Unigraphics name.

In 2002, the new version of Siemens Unigraphics, merged with I-DEAS software, was released and called NX, which means "Next Generation". In fact, it was the last version of the software released under the Unigraphics name. All further releases became known as NX. So the addition of I-DEAS functionality to the core code of the Unigraphics has become the basis of the existing NX product line.

Siemens NX / Unigraphics use a .prt extension, which contains 3D CAD parts.

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.