WordPress MU

I'm new to MU, but not WP. I'm experimenting to see if MU will satisfy a need.

We frequently use WP installs as the back-end / admin only for content mgmt - announcements and such. We invoke the loop within a separate page, outside of WP, to display entries that meet certain criteria.

Attempting to mimic this setup with my new MU install hasn't worked so far. Does MU change the manner in which I need to invoke the loop?

With regular WP, I simply do an include of 'wp-blog-header.php' from the blog I need and then run a function I wrote that looks for matching entries and displays via the loop.

Example page code:
http://pastebin.com/ma0c745

Example funtion code:
http://pastebin.com/m145ab473

Bumping in the hope that someone will respond ... Is this problem too rudimentary to request help on?

you may have to tell it which blog first. :)