I seem to be experiencing the same with the RN2483 pictail board. I only use the USB connection, I do get a serial port in Windows but no communication. I understand the default setting for the serial port is 57600 baud. I'm using putty, there seems to be a control sequence for break but it doesn't seem to work (btw: 0x55 = ascii char 'U' ?).
What would be the easiest way of pulling the reset pin. I didn't find any description of (or reference to) the PICtail pin's in the user guide. If there is any generic document about the PICtail interfaces?