While this recommendation isn’t fog specific, I think I would take this approach.
You have 1.2.0 working right? If so leave that system in place for a short time. It is working and the school can deploy.
Take a new machine (desktop with a dual core and 4GB of ram). Install Centos 6.7 on that system. Its in the redhat family so you should not have much of a learning curve switching from fedora to centos. Do a minimal centos install. Just be aware that there is no gui with the minimal install so you will have to use putty and/or the console for configuration. Ensure you update the computer to the latest patches using yum. Then download and install the latest svn trunk directly onto the system. Do no upgrade from 1.2.0 go directly to the svn trunk. This will ensure there are no remaining older bits on the system. Then just follow the installation instructions for centos. Document your steps, step by step so you can create an installation manual and have a history of changes. Once you get this second “clean” system built are you are sure it is configured correctly, change the dhcp options to point to this new server. If something goes wrong with the new server then just change the dhcp setting back to the working 1.2.0 build.
Once you have the svn trunk version perfected then resetup the main server. I can tell you that installing fog on Centos works and works well. Centos isn’t leading edge like fedora, but for servers you want stability over a fancy gui or latest hardware support.
Again this is only my opinion and how I would approach the problem.