Not everyone can include the full ext-all.js file on their site. This tool will allow you to build your own custom ext.js with just the things you need.
Dependencies will automatically be included in the correct order even if they are not selected - with one exception. If you choose a feature that adds functionality to a core component then you will need to choose to include the core component. For example, if you select "Grid - Editing Support" you will also need to select "Grid - Core". Please report any build issues in this forum thread.