The expand/collapse down-arrow icon (triangle)

1. Open the Articulate app.
2. Click the tiny down-caret arrow thingy and select Other Versions...
   
   

    

3. Select the desired version from the list.

Two things:

• This will uninstall the current version. You'll have to reverse the process and pick the most recent version to get back to it.
• The down-caret thing you have to click is invisible unless you float the mouse over the exact right spot on the window, which I find really irritating.