Confusion on Social Theme Customization

I need some direction on how to set the Social theme to dislpay 3-solumns throughout the entire site. I've set 3-column for both the blog & homepage layout settings in Theme Options. So when viewing the site as a non-logged in user I see 3-columns. I also want the Activity Stream to be the first page loaded for logged in users so I've set that under Settings - Reading. My goal is to simply have Left Sidebar - Activity Stream - Right sidebar. Is this not possible with the Social theme? Here's my demo here:

Any responses appreciated.