Rainbowduino Serial

What happens then if I want to control just one rainbowduino but high speed (115200Kbps)?
The datasheet says that it is possible but then there is no sample code available on that?

In addition, I think it would be possible to have several slaves in series, each of them with an identifier ID and using flooding to send the commands to all of them, then only the boards with the specific ID would react to those messages, maybe it would require some buffering, …