This section explains many of the things you might want to do with Balsa.
You can create new local and IMAP mailboxes by right-clicking in the mailbox list and selecting New Mailbox. This will start a dialog that will let you name the mailbox and specify its location.
To create a new POP3 mailbox, go to the configuration dialog, select the Mailboxes section, and click Add in the POP3 area. A dialog will be displayed that will let you set up the new mailbox.
Note: Under Sawfish, this dialog has been known to become obscured, causing the appearance that Balsa has locked up. Move the configuration dialog and see if the new dialog was hidden.
Note: The mailbox may not appear in the list immediately, or in the current session of Balsa at all, but it exists. Yes, this is a bug. The best workaround is to make the mailboxes outside of Balsa, using touch or maildirmake
The easiest way to move messages around is to select them in the message index and use the Transfer context menu. It will let you choose a mailbox in the mailbox list and the messages will be moved there.
This can be done. It's ugly, but possible.
First, create the IMAP folder as you want it configured. It will appear as something like "INBOX on host.domain.org". Exit Balsa. (I told you this was bad.)
Open up ~/.balsarc in your favorite editor. There will be a visible organization to the file; find the place called "Accounts". There will be at least five definitions that look like "Inbox = {Type = local;Name = (etc.)". There will also be one that says something like "m1 = {Type = IMAP;Name = (etc.)". Edit the file to replace "m1" (or whatever number) with "Inbox", and it would be wise to change the "Name" field to "Inbox". Change the Inbox entry to be the opposite; Inbox becomes m1 and Name becomes Local Inbox (for example).
Close the .balsarc and restart Balsa. Your Inbox will now be an IMAP mailbox. Hopefully you can figure out how to make your other mailboxes IMAP-based from these instructions.