You can add additional images and assets to your HTML pages by uploading assets to Uscreen.
To upload an Asset:
-Navigate to the Customization tab and click on Advanced
-Click Upload Asset
-Click Choose files and select the file you want to upload
-Confirmation of successful upload will appear and you will be redirected to assets list
-All uploaded assets will appear in the assets list
-Click on the blue file icon to copy the file URL