The % field specifies the desired intensity for each event. Values range from 0% (off) to 100%. Theme events are limited to ON or OFF. Using the scroll wheel, set the PERCENTAGE for the group(s). Multiple events can be created to initiate/change various intensities but must be designated to "off" using a separate event in order for them to extinguish.
NOTE: Make sure you have OFF intensities set for the groups/themes or the program will continue to run without shutting down.