[bug] late game prevention of movement

Several army units are unable to move even though the unit icon and path tracks are green and the next-turn button is not highlighted. Right-clicking on the desired, valid square will not allow movement. I have not tried other methods of movement than the mouse.

Indication that it may be on my end if I see this again: Try unplugging USB devices. I have been getting intermittent interference with the logitech wireless antenna.