You can display the leaderboard on any post/page using the shortcode [WpProQuiz_toplist 1] – where 1 is your quiz ID.
Do you use custom permalink structure? If yes, try to revert it back to default and save. Then get it back to your custom structure again. See if that could fix your problem.
Better use a plugin. There are lots of plugins out there, just search. I use Google Analyticator and it does the job. – http://ww.wp.xz.cn/extend/plugins/google-analyticator/
