No intensity when recording playback with effects V3.

I have 12 dimmer channels driving LED ‘stars’ through a decoder. To make them flicker I have faded them up and applied intensity flicker effect with fan and reduced depth. It looks as intended. I then recorded it to playback 19. From full clear I raise playback 19 and playback master. LEDs stay out but effect symbol appears. Manually raise the channels and they flicker to an extent governed by playback 19 but 19 doesn’t seem to have stored the original intensity values. It was recorded ‘including’ intensity/colour and ‘selected channels’ only. What am I doing wrong?