Using the Old Control System

[Breakaway3937]

We are looking to run our 2014 robot off the pre 2015 control system. I was just looking for a little help before we dive it.
1) Will the firmware load to the old cRio-FRCII? Do we need to load up the new firmware at all?
2) Will the most recent version of Labview still download the code properly to the cRio-FRCII?
3) Can we use the latest control station?
4) What about firmware on the router? Will we have communication issues between the controller and the router if it has the latest Rev. B firmware on it?

The robot isn't completely back in action, just wanted to get everything in order. I have tired to search, but couldn't find a great, clear answer. If anyone has found a better thread, please post the link in here. Just trying to make some use out of an old the old cRio-FRCII controllers. Thanks!