Hi Zerebrush,
It looks like the setting you want is available in the game options.
From the manual:
Enable edge panning: This allows you to push the camera in any
direction by moving your mouse to the edge of the screen. If set,
you can also set the Panning Speed bar anywhere from -3 (slowest
panning) to 3 (fastest panning). When this is disabled, you can still
move the camera with the arrow keys.
