Making a project sequential or parallel
Some projects consist of actions that can be done in any order, like picking up items at a few different shops; these are parallel projects. Other projects require one action to be done before the next one starts, like building a papier-mâché pterodactyl; these are sequential projects. In a parallel project, all incomplete actions are available, and the “next action” is just the first one in the list. In a sequential project, only the next action is available.
Whether a project is sequential 
or parallel 
is shown by the pair of arrows by the right side of its row in the outline. To switch to the other type, just click the icon. You can also choose a type from the inspector. If you find yourself using one type much more often than the other, you can change the default setting in the Data preferences.
or parallel is shown by the pair of arrows by the right side of its row in the outline. To switch to the other type, just click the icon. You can also choose a type from the inspector. If you find yourself using one type much more often than the other, you can change the default setting in the Data preferences.