How to set activity stream as Home page on Blogs MU theme ?

Can anyone tell me how to set the Activity Stream page, with sidebar as my home page on the Blogs MU theme.
When I set it through the settings, it comes up with a 404 error page not found.

I have searched and the only thing I can find is for the default theme and I can't figure out how to make the file edits for Blogs MU using the same method.

While I'm at it, how can I put the sidebar on the right instead of the left?

Any Help?