How to zoom in Captivate

You may also find this video helpful as well.

Adobe Captivate - How to Use the Zoom-In Feature in Your Video Demos

In Adobe Captivate there are two ways to record your screen. The first is software simulation. This creates a series of screen captures and records your mouse movements and keystrokes so that it can be later published as essentially a movie. During the recording, you can setup automatic or trigger pan and zoom to follow your mouse movements.

The second way in Captivate is to use video demo to record your screen. Once you have recorded your video you can then select points along the timeline to zoom and subsequently pan around your video to focus your learner into key areas of the screen. For the first year and a half, this is how I recorded all my YouTube tutorials.

Here is a tutorial where I demonstrate how I do this using Adobe Captivate:

Adobe Captivate 9 - Make a Screen Grab Movie Using Video Demo Feature

Did you look at the Zoom learning interaction? At least if you are talking about a cptx-project.

Video Demo projects (cpvc) have a dedicated editor with nice Zoom and Pan functionality.