Can't change inputs in Logic 9.1.3 with Presonus Firestudio?

I'm new to Logic, but I've read the manual, taken a Lydia training course, and I still cannot change the input selection in Logic. I've successfully tested the gear on my old machine using Digital Performer 5, but I got Logic 9 now so... What do I do?
On the channel strip, the Core Audio selection is grayed out on "Audio 1" and when I choose a template, everything defaults to "Audio 1," in other words, the first input on the Presonus Firestudio Project. I'd like to change it to "7," for example, or anything other than 1. And yes, I've checked the Audio Preferences and set the Presonus as the input device.
My Mac is a MacBook Pro, running 10.6.7, 4 gigs of RAM. I've updated to the latest driver for the Presonus, and the system needs no software updates. It's not running anything other than Logic. As a test, I even loaded Logic onto the "old" Mac in order to see if I had the same problem, and I do, so it seems to me that it's a Logic problem. Thanks again for your help and I hope to be up and running soon!
PS I should also point out that I can create new tracks and assign them to the inputs on the Presonus that I want. However, I'd like to change the ones that are already there... I am supposed to be able to do that, right?