Craig,
Here are the documentation on using charts:
[url]http://www.taskmanagementsoft.com/products/taskmanagerpro/help/ui-charts-panel.php[/url]
http://www.taskmanagementsoft.com/products/taskmanagerpro/help/how-to-make-graphic-reports-on-task.php
http://www.taskmanagementsoft.com/products/taskmanagerpro/help/how-to-make-graphic-reports-on-task-group.php
Probably you are right and we need to better document this feature.
When I want to make a chart I usually go the easiest way:
1. I select Task List view
2. I drag&drop the required column header (group tasks by this column)
Ex.: If I need to see how many completed tasks in comparison with incompleted, I drag Status column header, drop it to the space above the grid and select Pie Diagram on Charts panel.