On page Services - Content, you can upload your own Wallboard logo file(s).
Click Add Wallboard logo, define a name for the new row (this will appear in the listbox under Wallboard Display settings) and optionally a Description and click Save changes.
Then click the upload action button to open the Upload window.
Click Add logo, select the correct file (png, jpg, bmp) from your computer, and when you see the file name in the popup window, click Upload. The staus will change from Ready to Finish after a short while, and then you can close the window.
To see an uploaded logo file, click on the play button. To upload a new (replacement) file for a defined logo name, click on the upload button and choose a new file.