Replace the Old Staff+.jar with the new Staff++ jar.
A new directory StaffPlusPlus will be created.
In the config file change storage type from flatfile to sqlite or mysql:
#Type is how it will store either a sqlite or mysql
Staff++ dropped support for flatfile storage. We now support MySql or Sqlite. We do not yet support a migration from flatfile to the SQL database. This means you will lose your previous reports/warning should you have them. This is a one time loss and everything from this point out will always be gracefully migrated.
All other properties should be migrated automatically if you are using the latest version of Staff++.