When you add an episode for Nanacast hosted membership content, below the content input box is a list of available tags. Just below that is a blue link that expands another list of more available tags. Those tags can be used in place of URLs to hyperlink the dynamic episodes. 

You must first create the episode you want to hyperlink to, and then you will find the episode URL tag for that episode in the list, which you will use as the URL for the hyperlink.