The default settings in the Gantt don't show the critical path. This is
because in the "early" days of Project for Windows, MS support line got
a lot of calls asking, "How come Project it trying to tell me what's
critical on my project? The software doesn't know that, only I know
that." They were confusing the conversational term and the scheduling
term. In one of the early versions (don't remember which one now), they
"hid" the CP and made it so you have to turn it's display on.
To turn it on, click on the Gantt Chart Wizard near the right end of
the standard toolbar. You have to tell it to go ahead and run it. I
think it's the second window where one of the choices is "Critcal
Path". Select that, and then either "Finish" or continue through the
Wizard if you want to make some other formatting changes to the default
settings. Now the critical tasks will be in red.
By the way, it's not "free slack" being zero that makes the task
critical. Free slack is the amount of time a task can slip without
effecting any other task. It's "Total Slack" that determines
criticality (the amount of time a task can slip without effecting the
end date of the project).
Best of luck!
