Previously I reported how Scrivener was disappearing from the screen here:
Scrivener Disappears During Tutorial [size=85](<- Link)[/size]
After going back into Scrivener again three times to see if a pattern could be determined, a process that repeats the failure happens while the Tutorial’s Part-2 Organization is displayed, and the “Group Mode” segmented control is toggled through from the “Corkboard” to the “Composite”, to the “Outliner” and then All Off mode.
See Link for installation details.