Hi Mike,
Open the 2D map (key 9) and in the bottom right hand corner of the screen there are two icons, a box icon (which I believe is supposed to look like a HST) which will be either Blue or Red in colour and next to it a Monitor icon.
If the box icon is already Red, then by holding down the right hand mouse button and moving the mouse you can look around the 2D map, also zoom in and out by using the mouse thumbwheel (if you loose the zoom facility, exit and re-enter the 2D map).
If the box icon is Blue LMB click and it will turn Red.
Hope that sorts you out.