Sometimes key shortcuts (like Z,Q,W,E,R,1,2,3,4,5) don't work

Sometimes key shortcuts (like Z,Q,W,E,R,1,2,3,4,5) don’t work .
It happens after base mutation, in 40% of cases the mentioned keys are not working.
I can fix it by clicking in eteRNA editor area (could be focus related bug?).
But it is tedious to click everytime when you want use key shortcut :).
My browser is Firefox 8.0, and Adobe Flash Player

Happens to me too. It seems after about 4x of adding in a G and then removing it, is the most common time for me. Then you have to go back to keyboard and remind Eterna what it’s doing.

Yes, it is like the keybord looses the grip on the puzzle. Happens often. I then click with the mouse somewhere on the screen outside of the puzzle motive, and that reconnects the grip on the puzzle. Then I can use key shortcuts again.