[JimmyTrivette]

In settings, there is option to set "effect" smooth and to select "transition duration (ms)" to some value. This means to turn it off smoothly....

you can see it in this video:

https://www.youtube.com/watch?v=00ipLsPvGoQ&t=250s

I don't have it... my settings does not show all options via kodi add-on menu. I need to set it up by editing settings.xml.  

I think it is this setting, in ms, no more than 2000ms:

<setting id="bulb_1_pause_duration">400</setting>

ofcourse, depending on the action, i.e. bulb_1_play_duration, bulb_1_stop_duration etc

Yeah, this thing works but what I am trying to do is to make the bulb turn off gentle.. Switching between play/pause/stop works perfect I just want to add the same effect to switch off.