For a GUI codeplug editor/extractor/installer and firmware updater, see: https://www.farnsworth.org/dale/codeplug/editcp.
There is also a command line codeplug extractor/installer and firmware installer at https://www.farnsworth.org/dale/codeplug/dmrRadio/downloads. Its only documentation is obtained by running "dmrRadio -h".
Source code and information about the codeplug software suite may be found at https://github.com/DaleFarnsworth/codeplug.