RF missing characters
In your first sketch, you have

int ledPin = 13;
int rcvPin = 13;


Did you mean both those to be assigned to the hardware LED on the Nano? (Pin 13 is the on-board LED). If so, why? With all the pins available to you.

The other thing I don't understand is your use of: 

byte message[VW_MAX_MESSAGE_LEN]; // a buffer to store the incoming messages
byte messageLength = VW_MAX_MESSAGE_LEN; // the size of the message


It will always just be one byte, won't it? 

Why not use available()?

http://arduino.cc/en/Serial/available

I see this was posted six months ago - no doubt you have already solved it.