While playing yesterday, there was a point at which I was unable to right-click to send my unit to part of the map, but potential lines of movement would appear in other directions... but when the mouse was held over a different part of the map, quite a ways away from where my cursor was. It was also not possible to trigger the auto-explore feature for the unit at this time, and the cursor would not register clicks on other parts of the UI. Could not end turn because it said I had an idle army. Was forced to quit.