When making a tutorial to show the user how to group related questions when they save them I ran into a possible bug.  The problem is when I select the create charts after selecting the main category for all of the questions, the select * appears with all the others.  It only seems to happen when I select a main category that has an empty subcategory.  The following are the steps I took:

How To Group Multiple Questions into a drop down
This sections will explain how to group your saved queries so that you can differentiate yours from others and group up questions that have commonality with each other. This section will ask you to do things that were covered in previous sections. Although the steps for these techniques will not be explictly laid out, links to relevant sections will be provided in case you need a refresher on how to do something.
1. In the questions tab reveal the question editor, by clicking and dragging on the the three lines below create chart up.
2. Select example_cars from the list of tables.
3. In the Question Name field type in your user name.
4. Click add with the query field empty
5. Click on the new question that you just created
6. In the Question Name field type in Chevys
7. Click add child.
8. In the questions area note that the question with you username now has an arrow next it. Clicking on the arrow with expand it revealing the Chevys questions group. This process can be repeated over and over to make subgroups as needed.
9. Use the basic query builder to Create a chart with all cars
10. In the Query Panel select the make column using the Column Selector
11. Click on the Chevy bar on the chart and click the New Widget button.
12. Change the name of this new panel to All Chevys
13. Click on the Questions Tab select the example_cars chart and select the subcatergory you made for Cheveys
14. Type All Chevys in the Questions Name.
15. In the, All Chevys Query Panel, select Set Query Builder from the drop down in the lower right and click Go.
17. Click Add Child
18. Now select the Color Column from the All Chevys panel. Click the bar for Red on the chart and click New Widget
19. Change the name of the new Panel to Red Chevys
20. Make sure you still have example_cars and you user name->Chevys question group selected.
21. Type Red Chevys in the question editors name field and use the set Query builder button.
22. Click add child in the Question Editor
23. Close all the query panels that are open so that only the query builder is open
24. With the example_cars table selected, select your user name from the questions list by checking the check box
25.Click Create Charts

Instead of creating two charts it creates three, one being the select * which does not appear in any of the saved questions.  Some other improvements to simplify things for the users would be if when you click set query builder it automatically makes the name whatever the title of the Panel is.  Also when you create a panel the question name should appear as the panel name.  Currently there is a lot of bouncing back and forth between the panel and the query builder.