>Cans Thunderbird store all attachments in a designated folder? If so how is this done?

As far as I know, unlike Eudora, Mozilla Thunderbird does not store attachments separately from the message to which they're attached. You should still be able to extract the attachment from the message.

One problem with the method that Eudora uses is when you have attachments with filenames that conflict with any existing ones, Eudora ends up renaming the attached file to prevent collision -- so the original filename isn't preserved. Another disadvantage is risk of file clutter if you don't clean out the attachment folder after deleting messages. Also, relating to the other problem I'd mentioned with dealing with Asian language within Eudora -- typically attachments often end up being irretrievably mangled (sometimes they end up as part of the message text). On the other hand, I've had a bit more success when dealing with Thunderbird in this situation.