Currently, you can modify the default image height and how many images you download.
The reason it won't work directly from the HTML link is that the javascript calls XMLHTTPRequest() which only allows requests from the server the page is on. But the whole point of the script is to download http://www.livejournal.com/stats/latest-img.bml which is on the livejournal.com server. However, the web browser allows it if the html file is saved on your local computer. The javascript uses the now-native XSL processors to turn livejournal's xml document into friendlier html.