If they all blink really fast it means the ESC is in LVC mode. Chances are you set the LVC for a certain voltage and you are using a lower voltage pack, or something like that.
the green, yellow and red all blink togather about 5 times a second which is pretty fast, but idk how the LVC could be kicking in when im using a fully charged pack, i even checked the voltage with a little individual cell voltmeter that plugs into the balance port and it said 16.80V. Unfortunatley i can't find my castle link CD, it was installed on my old computer but it crashed, but i remember setting the ESC for 4s LVC when it was being used. i hooked it up to a reciever but not to a motor and the LED's didn't respond to throttle or brake inputs.
you can download the castle link from castle's download page. I'd put the latest firmware on there, auto lipo 3.0v/cell. I would also plug into a motor. if it beeps once or twice a second, it is has no signal to it, which could signify a broken reciever.