To view the details and/or history of a request, double click any cell of the request or click any cell to produce the action bar, then select View.
This will produce a new window showing all the details of the request plus the relevant cumulative times for the request, warnings and requirements.
Click the History button to view the history of the specific request.
Click on the Details button to go back to the Details view or click on the 'x' to close the window.