There is a distinct and important difference between "Black" and "None"
If you use None for an effect (effect 1 and 2), then Nutcracker will write NOTHING in that space for those channels. This is tremendously useful for those people who import an LOR sequence and want to add Nutcracker effects. You would use None for all the times except for those seconds when you want to overwrite some LOR data with Nutcracker data. I did this with the Pixel Rectangle on my roof frequently. Some LOR sequences already had good data for that rectangle but from 1:32 to 1:58, I wanted something different that would have been difficult to create in LOR. So I did NONE from start to finish for that model, but added an interval from 1:32 to 1:58 with my effect. When I saved, no LOR data was overwritten except my 26 seconds.
If you use Black for an effect, Nutcracker will literally "black out" that time period for that model so that nothing on that model lights up.