When i first use the Step sequencer to program a beat then i see all the rows, one row per note.
I maybe add then some rows or delete some, as i need it.
But if i close the step sequencer view and then after some time reopen it, all the row setup is gone and only the used rows will be shown.
To develop or change the beat over time is really hard or uncreative by this.
How to solve this, did i miss some settings?

I ran into something very similar so I am adding this here. I started creating a drum track (SI Drums) in the track piano roll view, and then converted that to a step sequencer pattern. As for the OP above, only the used notes show up as rows. Is there a quick way to populate the step sequencer with all available keys / rows?