I'm getting the same problem, hovering over the slow download option doesn't show any URL but the premium option links to a URL. I can't click the slow download button nothing happens. My Java is up to date, adblock is disabled on the site as well.
Would like to see someone working on an update for Captive using this game. Any takers? Personally think this game screams out for an update and the Grimrock engine seems like it'd be a really good starting point to remake this classic Amiga game. Obviously it'd need a lot of mod work on the graphics/enemies/weapons etc.