The tutorial page explains you how to setup PowerViewer. After setting up PowerViewer, the following steps explain how to configure it to allow a slide show to run on secondary monitor while you continue to perform other tasks on primary monitor:

Step 1: Select the Presentations tab.

Step 2: Click the box next to the Presentation file box. Locate and select your presentation file and click Open button. You would find your presentation file listed in the Presentation file box.

Step 3: Click the Add button to add the presentation file to the file list:

Step 4: Select the Settings tab.

Step 5: Select 2 in Start on monitor box.

Step 6: Click Start Show button.