When clicking on a link that jumps to an anchor, the name of the anchor is passed via the URL ( mywebsite.com/index.html#anchor) In the case of openGoo, nearly all of the 'pages' that you go to are done via some ajaxy javascripting. That means that even though it appears that you are visiting different pages, as far as the browser URL is concerned, you're not moving.
So the links that you click on inside of opengoo that point to named anchors never make it to your browser's URL bar, so the anchors won't work.
This is also why your 'back button' won't work in opengoo.
You're always better off viewing an HTML document in it's own browser window rather than trying to see it inside of some other construct.