Uninstall Editabula, then install a new version.
Normally, that's it.
Note that if you upgrade from 1.4 or the earlier versions to 1.5 or the later versions, you need to convert database files by using Export/Import Objects. The procedure is:
1. Export all the objects per database (to backup file).
2. Uninstall the old version.
3. Install the new version.
4. Create database and import each backup file per database.