In Source Definition of your import task, specify the name of your Trello list to load cards from instead of Enter your list name....
In Mapping Definition of your import task, for the AssigneeId field, specify the email of TMetric member who will work with the task instead of Enter TMetric member's email....
For the ProjectId field, specify the name of TMetric project within which the task will be executed instead of Enter your Project name....