[TylerHarmon]

If your code is crashing when you try to initialize the NavX, it probably is not properly communicating with the roboRIO. If you try to read from it before it is booted, you will also get a Null Pointer Exception. Just check if the value you want from the NavX != null before you try to do anything with it.

Most likely from what I have read here, you are not properly communicating with the NavX on an electrical side, or it is wired properly but you are trying to communicate with the wrong protocol.