The configuration of a calendar page is very simple, because most of the customizations are performed by editing the Groovy source of the page.
You can modify two parameters, the first influencing the agenda view, the second acting on the month view.
Events per page is the approximate maximum number of events that you want to show in the Agenda view. The agenda will always try to show all the events of each day up to the maximum, so it might happen that a few events more than the configured maximum are shown.
Max events per day influences the height of the cells in the month view. Each cell will be rendered tall enough to contain the specified amount of events.