Thanks Paul - after I read your post, I played around with this a bit on my own and started to get somewhere. Then Vince called me and walked me through the fix. What I didn't understand was that you need to adjust the valve in tandem with the pump. Needless to say, I spent the rest of the day pulling beautiful shots.
I couldn't be a happier barista; I can now focus on promoting my business. Lemme tell you, I was pretty stressed out during the whole ordeal with 50lbs of coffee sitting around (yes, I had my home e61, but there's really no comparison between the 2 machines in the commercial environment).
Anyhow, thanks for all your help!