If you send a message to the address firstname.lastname@example.org, (for non-subscribers, you send a message to email@example.com) everybody will receive it (you can check who everybody is in the menu "Review").
You can read and place documents, create files etc. in the menu "Shared web".
You can change your password in the menu "preferences".
You can see all the messages in the menu "Archive" : if you choose "chronological", the messages will be classified by date, if you choose "thread", the messages will be claddified by follow-up of the conversation.