An editor window will open. You can delete most of it (it will be green and commented out). Just keep to the structure above. The important bit is that you type in:
replacing <number> with the numeric value between 1 and 20 (inclusive), and keep the function declaration intact.
Output your Hype document as HTML 5, and return to Freeway. Set up Freeway to use the Hype document as detailed on this page.
In Freeway, select the Hype Object Action item on your page and open the Actions Palette. Open the Target Chain Calls disclosure triangle.