The author of this plugin has indicated that they are not longer fielding questions and providing support for this plugin. The plugin is provided as-is.
You may still post a question, but any responses will come from members of the community, not the author of the plugin.
You cannot open plugin, or theme, files on your computer. You must import the file into your forum. To import a plugin, go to Admin -> Plugins -> Manage and click the Import Plugin button, then just follow the instructions in the popup.