Coverage slots in VSys Anywhere can be much less confusing: they display in a calendar format where you can see the various openings available along with who's assigned. You create and edit coverage slots from VSys Anywhere just as you would any other slots, but you manage assignments in them with the Job/opportunity lookup (slot coverage) tool, specially configured for coverage slots.
Looking at these assignments and slots in Agenda day or Agenda week mode is usually the most intuitive. In the example below, we see two NODA slots: one starting at midnight, needing one volunteer. The other starts at 4:45am, and if we hold our mouse over it we'll see that it needs two volunteers. The reason? Irene Gomez is scheduled from 8:45pm the previous day through 4:45am, so she's covered that portion of the slot's needs.
Slot, still empty
Assigning a volunteer
From a job slot, click Assign a volunteer to make a new assignment. Select a Volunteer, then the Start date/time and Duration. Note that VSys won't let you select a Duration that would have the assignment run past the end of the current opening.