[AccessD] Needing a Fourth Conditional Format

Dear List:
 
I'm making a Gantt chart of scheduled classes for a client - an interactive
form where he can scroll forward and backward by a day, a week, a month, or
a year.  The course statuses are Scheduled, Complete and Cancelled.  The
bars showing the date are color coded red, green and brown. And it's a
continuous form.
 
Working well.  Until...
 
The user wants to be able to mark a course a Tentatively Scheduled
(reserving the space, but not yet booked).  So there's a check box on the
Course Schedule form for tentative.
 
However, he wants the tentatively scheduled class to show on the chart with
a different color (I'd go with pink but that's not important, now).
 
It looks like I need a fourth condition but of course conditional formatting
only give you three conditions.  
 
I"m stumped (without redesigning the approach of the whole form - not a
pleasant prospect). Any ideas welcome.
 
MTIA
 
Rocky Smolin
Beach Access Software
858-259-4334
www.bchacc.com <http://www.bchacc.com/> 
www.e-z-mrp.com <http://www.e-z-mrp.com/> 
Skype: rocky.smolin