From the introduction:
This campaign is a set of linked scenarios, to be played in order. However, if modified slightly, they can also be used separately as mini-adventures.
As mini-adventures, each should take only an hour or two to play. Although the Game Ref may enhance the stories somewhat to make them longer if he, or she, wishes. While the full campaign will probably last for at least several hours.
The suggested character level for this module is 5th thru 7th. Although, like with all Orbit campaign modules, the level of challenge may be altered quite easily by the Game Ref by simply adjusting the level of NPCs and other encounters, many of which are listed in the Aliencyclopedia at the back of this module.