Hi Betty,
I can answer much of those questions for you.
1 & 2. It will run on any flavor of Arena, it is the ability to install it that is the discriminator. Currently it can be installed on both Premium and Select as long as they are self hosted. We are working with Shelby Systems on being able to install on Shelby Hosted clients.
3. The way the module works is that it emulates a kiosk. If that kiosk is properly configured to print labels it should work. I'm not personally aware of any churches printing labels through it. I too would like to hear from any on how they are using it.