Hi, I am a software engineer working in an oil and gas consultancy firm based in United Kingdom.
Recently, I have been developing 3D software, which is capable of handling various 3D file formats, including OBJ, DWG, DXF, STP, IGES, STL.
Also, I have specific tools to open Navisworks NWD file and export to AutoCAD DWG.
I would be very happy to convert some of your sample NWD for your evaluation.
I look forward to hear from you soon.
Thank you.