Hello captain_ bond!
I'm not a moderator but for the Pm outbox, I believe that all you have to do is click on reply on the top right hand side of the message you would like to respond to
To send a new message, on the main page just place your cursor on "MY MESSAGE" and a drop down menu should appear! Then just click on "SEND A MESSAGE" When you have made a message and are ready to send it, just go to the bottom of the message box and off to the right hand corner under it you'll find "SEND MESSAGE", "PREVIEW MESSAGE" and "SPELL CHECK", just click on SEND MESSAGE
As for the number icon, I'm afraid I can't help you. I get them but the minute I read then and move on the number disappears!