Most of the functionality of Mail Archiver X can be controlled with the Toolbar, which sits at the top of the main window.
Add: Shows Wizard to add a new mail client or an IMAP account to the archival.
Setup: The Setup controls what, how and when Mail Archiver archives.
Archive: Starts the archival for the mailboxes of the activated email clients and IMAP accounts.
If the open archive is different to the archive selected in the Setup then you will see a dropdown menu. You can then select one of the archives for archiving. In the screenshot my open archive is directly in the User folder. The Setup has the archive in the Documents folder.
Archive Mbox: Shows a dialog to select files for archiving and then archives the selected files.
Open: Select a file to open.
Print: Print a mail.
Export: Exports the complete database, the current mailbox or the selection. You can select the options.
Delete: Move the selected Mail to the Trash mailbox.
Filter/Delete Filter: add or change a filter and remove a filter.