To setup a text carousel, do the following:
  1. Create an image that contains the text you would like to display for the carousel.
  2. As a Page Manager, go to onMessage, hover over Website, and select the site being worked on.
  3. Go to the Page or Master Layout that has the photo carousel. 
  4. Drag a Photo block onto the page, and either find the photo category that has the text image, or create a new photo category and add the text image to that category.
  5. After the photo category is selected, click the paint brush icon to to go into the style selector, and in the drop-down find the carousel style to apply to the photo block that was just added to the Page or Master Layout. 
The text image will now rotate like a normal image.