Breathing light:

edit /etc/mce/mce.ini (have a backup first; added values in BOLD):

...
[LED]

# List of patterns for the LED functionality
#
# A list of all pattern names that should be configured
LEDPatterns=PatternPowerOn;PatternPowerOff;Pattern Communication;PatternCommunicationAndBatteryFull;P atternBatteryCharging;PatternBatteryChargingFlat;P atternBatteryFull;PatternDeviceSoftOff;PatternDeviceOn
CombinationRules=CombinationCommunicationAndBatter yFull
....
[LEDPatternNJoyRM696]
...
# FIXME: sloooooow breathing
PatternDeviceOn=254;0;0;4000417f41ff41bf0000
PatternDeviceSoftOff=253;0;0;4000413f41bf5f900000

PatternPowerOn=9;3;0;4000087f087f01ff01ffc000
PatternPowerOff=10;3;0;4000017f017fc000
PatternCommunication=30;1;0;4000027f027f02ff02ff02 7f027f02ff02ff41ff0000
PatternBatteryCharging=50;4;0;4000417f41ff41bf0000
PatternBatteryChargingFlat=50;4;0;407f5f005f005f00 5f00400041ff0000
PatternBatteryFull=40;4;0;407f0000
...
I have used the value from PatternBatteryCharging; can be modified accordingly.

PS: for breathing light is no need to have "LED Event Notifier" and "Inception" installed. For extra LED notifications above programs are (still) mandatory.