space bar and arrow keys will not function
The space bar and arrow keys will stop functioning if the F9 pallets box is closed by clicking on the red button in the top left corner of that box. Instead, hit the F9 ket again to close the F9 pallets box.
Comments
I don't doubt that there might be some sequence of events that leads to this, but I can't reproduce the problem. Maybe it depends on that last thing you did before closing the palette?