FeatureCAM uses three .ini files to store your settings:
The ezfm_mfg.ini file contains default values for both inch and metric attributes. For example, there is an entry for zrapid in inches and also an entry for zrapid_mm in mm. In general, the name for the metric attributes is the same as the inch name, with a suffix of _mm.
Three items affect the communication with the ezfm_ui.ini and ezfm_mfg.ini files:
You can make a backup copy of the .ini files before you save any changes; this way you can revert to the default settings if something goes wrong. Alternatively, you can delete the .ini files; when you restart FeatureCAM, these files are recreated automatically with the default settings.