Holding the middle mouse button and dragging will pan the view.
Holding Shift while middle-dragging will rotate the model about its central point.
If you do not have a middle mouse button (e.g. using a laptop with a touchpad) the same effect can be achieved by holding Alt and dragging with the left mouse button - i.e. Alt+left-drag to pan, Alt+Shift+left-drag to rotate.
The Lock Rotate button found on the toolbar can be toggled on. When this mode is enabled, middle-dragging will rotate the model even when Shift is not held down.
Scrolling using the mouse wheel or the vertical scroll section of a touchpad will move the camera towards/away from the model.
Pressing the Home button will reset the camera to its default position.
Pressing F5 will refresh the model to take into account any changes that have been made to the model that are not displayed.