You can create a watermark image by setting the transparency of an image.
To create a watermark image:
Open a Captivate movie.
In Storyboard view, double-click the slide to which you want to add a watermark.
From the Insert menu, select Image.
The Open dialog box appears.
Select an image or browse to a new location for a different image. Click Open.
The New Image dialog box appears.
Set the image transparency to 50% by entering 50 or a lower number in the Transparency text box. (A low number results in a dim version of the image and a higher number displays a brighter image.)
When you are finished, click OK.
The image is added to the slide.
Position the image on the slide as required.