You can see in this page a message about the successful completion of the import of Project Configuration and two text areas with information. The first one "Import results" shows statistical results of the data import for each imported project, identified by its name:
It would also show warnings, if any, that do not impede the import of project data but might cause the loss of some specific information (one issue, an attachment, a custom field value, etc.). Errors about the validation of the data backup or the mapping of data to the current configuration would also be shown here. If there were any of these errors, project data would not be imported.
The second one "Import trace", contains a sequence of the steps taken for importing data, and offers a much finer detail of the actions performed during the data import.
The button "Back to import complete project page" takes you back to the starting page, so that you can launch a new import of complete projects.
Under both text areas, there is a button labeled "Click here to see configuration import trace". This button opens a new page, as the one shown below, that displays the trace of the configuration import (remember that importing complete projects is done in two steps: first the configuration is imported and later the data and attachments). This is useful if you want to keep a record of all the configuration changes performed on the target instance.