I am trying the Candle for the first time and having some problems. If I set the first 4 leds on the candle to some color (index 0 length 4), the color is set. If I follow that call to setLeds with another call to set the second 4 leds to a different color, that second call fails with error CAN_NO_SESSIONS_AVAIL. It seems that after the first call to setLeds, any other calls fail.
It also appears that if an animation is started and then you redeploy without the call to start the animation, the previous animation still runs and setLed calls are ignored. You have to explicitly turn off animation before setled will set leds.