This file defines the relationship between the component and non-geometry files such as external spreadsheets, image files and other information for design automation. What is a KRX file? The KRX file type is primarily associated with Karaoke MIDI File. KRX file is a Siemens NX Reusable Component. Opening your KRX file starts with understanding which software uses the KRX extension. in my case I've edit KRX file, but for reuse parts that doesn't have, you have the ' create KRX'.