You can send the content from a persona. To see the Personas' menu, you need to click "Personas" at the top bar.
To change the persona who sends a content, click the persona's name that appears in the card. Select one of the personas from your list.
If you want to make that content to appears on your player's first login, right click the card and select "Publish on first login". The card will be now yellow.
If you reset the first login, upload the scenario and then log in, you should see the same as the screen shot below.
Notice that now the message comes from the persona, Frank. It looks more interesting already.