This page list all the course that are publicly avalaible. When you click import, it will create a new course on your INGInious instance. You will be admin of this new course and it will contain all the tasks and the structure of the imported course
Only the specified amount of tasks to be displayed will be shown to the user. There is no state: changing the amount of tasks per section, section position or section title will affect the effective task set a user will be displayed.