In order to create backup copies of complete Match! reference databases, you can copy (i.e. backup) the complete contents of a reference database index directory. The name of a current reference database directory is given in the right-most column in the Reference Database Library dialog.
If you would like to use/restore a backup copy later on, simply copy it to an appropriate directory on your PC. Afterwards, click the "Add" button in the Reference Database Library dialog. A "File Open" dialog will be displayed in which you can select the "Match! Reference Database" file (MatchRefDBInfo.mtn) that contains the information required to use the index files in the same directory. Please mark the file "MatchRefDBInfo.mtn", then press "Open".
In case you have administrator privileges, you will now be asked if you would like to make the new reference database available to all users (or only to you). Afterwards, the new reference database will appear in the Reference Database Library, ready for being selected for usage.