Removing Opportunities From the Opportunity Map
When you click an intersection on the opportunity map, the intersection dialog opens.
Each potential, current, and won opportunity in the intersection has an X icon. When you click this, the opportunity is removed from the intersection.
A potential opportunity is actually deleted and can't be added back onto the opportunity map.
A current or won opportunity is merely removed from the opportunity map, but the underlying Salesforce opportunity record remains. So the opportunity can be added back onto the opportunity map if necessary.