As you know Mountain Lion (OS X 10.8) unfortunately doesn't allow enabling web sharing in Systems Preferences anymore. If you want to use Presenter Player Pro with self-publishing in conjunction with Mountain Lion there are three options:

1) install Mountain Lion Server and enable the web server
2) use a series of Terminal commands
3) use the attached tool ("WebSharingEnabler") to enable (and disable) Web Sharing on the Player computer

WebSharingEnabler is free of charge, oPlayer Pro Self-Publishing; Web Sharing and Moutain Lion 10.8.x course, and comes "as is".
Important Note: You don't need (and shouldn't use) this with 10.7 (Lion)!