focus moves to other fields

[Jimmy Patrick]

Hi, 

I notice when I am typing in a clue, I have to be really fast. I am not a great typer or maybe I can't think fast enough, but if i stop typing, the focuse shifts and then i'm accidentally filling in the grid with gibberish, or I hit period, which now turns my lights to a dark, and I can never figure out how to switch it back and undo the mess I've made. Is there a way to stop it changing focus? At any rate, I love the software!