Hi John,
I tried to comment this sketch pretty heavily, but probably didn't think about the absolute beginner, my apologies.
RX_TOGGLE_PIN is just a pin that is toggled depending on the state, you can ignore it, not even sure what I had in mind for this pin.
For the additional RED/GREEN LEDs, if you take a look at the code, you will find this section:
if(LEDSTATE==LOW)
{
LEDSTATE=HIGH;
digitalWrite(LED_GREEN, HIGH);
digitalWrite(LED_RED, LOW);
}
else
{
LEDSTATE=LOW;
digitalWrite(LED_GREEN, LOW);
digitalWrite(LED_RED, HIGH);
}
As you can see, the LED_GREEN and LED_RED are toggled (only 1 is ON at 1 time) based on the state of the LEDSTATE variable, which in turn is toggled by the messaging between the 2 nodes loaded with this sketch.
It's a very very simple sketch illustrating how to ping pong a message between 2 nodes. This sketch is loaded on BOTH ends, just configure settings on each, give them unique IDs etc.
D10 (aka radio SPI CS) on Moteino is always used by the radio/SPI, it's hardwired to it.