You can modify time on the diagram.

Select a train by mouse. Blue selection boxes are shown. If you select a stop, a red selection box is shown there.

It's possible to modify time of the selected stop. Right click to see the context menu. And select [Station]-[Time Setting]. [Stop Time] dialog box opens. You can modify time and stop type. Keep in mind you cannot use this menu when you select two or more stops.

It's also possible to modify time using arrow keys. Press down key when a stop is selected to change the time later. Up key to change the time earlier. This method is valid when you select multiple stops.

Time modification with mouse is possible. Drag and drop selected stops to modify the times. This method is also valid for multiple stops.