BuddyPress.org

This is exactly the theme I was looking for and I want to use it for a new site I am developing at http://virtualcrowds.org/ which is currently running on WP3 RC2. The problem I am having is that, on a couple of pages, it looses the left hand column. Can you tell me how to fix this? For example, if I cick on a tag at the foot of a post or in the tag cloud, to search for similar articles, I get a page with “You are browsing the archive for *tag* but no left hand column. Also, my Links page shows no left hand column. Can you help?