MRF49XA Microchip Transceiver
The demo code is for a PIC18F87J11 and the C18 compiler, whereas you are using a PIC16F886 and some other, probably incompatible, compiler.

You will probably have more success if you use a PIC18 instead of the PIC16F886, with the C18 compiler. I downloaded the code, and apart from having to fix the include file location, the application built without any problems. You are also more likely to get assistance if you use the correct chip and compiler, either from people here, or on the Microchip forum.