Eudora Message Saving/Sending Problems

I'm new to Eudora on Mac. Recently I decided to download my Yahoo mails from the Yahoo server to my newly installed Eudora 6.x for easy management, but it landed in disaster.
(I have Yahoo Plus paid service, so POP is supported)

After all the necessary settings, I started to download (check mail) messages. The mails did come in but stopped after some 30 messages. But that's not my question here.

When I try to save a single message in Eudora to my designated folder on my hard disk, it only saves in plain text txt format without the attachment. How do I save a message natively?

2ndly, though I've read this on many posts but there's no simple solution, is that attempting to forward a mail from Eudora fails. It simply doesn't send with some error messages displayed. I've worked around with authentication but to no avail.

What do you mean by saving a message. Eudora downloads messages into itself, like any other mail client. BTW, Eudora is plain text. It is one of the few email clients still available that does not display messages in HTML. I use Postbox and love it.

Welcome to Postbox

Saving Private Message

Saving individual message means... save the downloaded message in a format readable by both OSX and Windows. Eg., drag a particular incoming/outgoing mail onto a thumb drive, and share it with your co-workers on their PC.