Lanes that disappear from Performances

[Rupert T Bear]

I've owned my Wavestate for about 18 months now.
Despite being something of a newbie, I'd like to think I've made pretty good progress.
I've been creating set-lists from my own performances, some edited random performances and of course factory performances.
What I can't understand is why some of the factory performances only play 2 lanes, when there's clearly 4 lanes.
Obviously the set lists only refer to the machine's bank or performances - but in some cases, both only play 2 or the created 4 lanes.
"Space Pad" is a good example. Four lanes become two?

Why??