With experimentation I am getting closer. Thanks. For my new tasks the only Show For information is just the Flag (e.g. Flag1 or Flag2) This seems to work. What I found however, is there seems to be a priority. I added three new columns (Flag1, Flag2 and Flag3) and create three new Bar Styles that have only Flag1, 2 or 3 in the Show For field.
If I set the Flag1 field to yes the bar style matches the Flag1 style I defined. But if I have both Flag1 and Flag2 set to Yes. It is the Flag2 style that is used. If I set all three to yes, the Flag3 bar style is used. I can deal with this.

New question. I want to set the bars length based on the start date and the end date. And I may need to change one of the these dates. But when I change the date I want the duration to change and not the other date. What I see now is I input start and end and the duration is calculated to be say 90-days. If I now change the start date, the duration stays at 90-days and the end date will also move. What do I need to do so that the duration will float as I change the dates?