A method configuration allows you to select and deselect from the content packages, processes, and categories available in the method library's set of plug-ins. The selections you make restrict the scope of content you use as a basis for defining your process. These selections also determine the content of the published web site which communicates your process to others in your organization.
Configurations are assigned names and saved so they can be reused at a later date. In addition to creating configurations as described below you can also simply copy-pasting a configuration by right-clicking the configuration that you want to copy and right-clicking the top-level Configurations folder and selecting Paste. You will get a complete copy of the configuration under a new name that you can modify for your needs.
If you reference an element in a package that is from another package, you can only see the full details for that element in a published site if the package containing the element is in the configuration. If the package containing the element is not in the configuration, the "offending" package is marked with a warning sign. You may always choose not to include the full details of a referenced element and ignore the Warning or Information message. As a result Composer will not publish any links to the excluded elements. If you want to fix the problem then click the Add Missing References button to automatically and recursively add packages containing any elements that are referenced in already selected packages. Since this is recursive, a large number of packages may be added, perhaps making your configuration larger than you want it to be.
If you have elements in a package that contribute to, extend, or replace elements in another package, it is an error if the base package is not included in the configuration. Errors are marked with a red cross. If you drill down into a plug-in or package marked with a cross you will discover the "offending" package and then you can find the packages you need to include to resolve the error. Alternatively you can click the Make closure by fixing errors button to automatically fix the errors by adding the missing base packages.
The Problems view lists and explains all errors and warnings in the configuration. You can right-click every individual message and select Quick Fix to get more detailed information and a proposal for automatically fixing the issue. You can also define Filters on the Problems view using the Configure Filters dialog that can be open with the button on the right-hand corner of the Problems view.