I haven’t been able to reproduce this error using the default twenty-ten theme that comes with WordPress. Can you try it with the twenty-ten theme and see if you still get the error. Based on the error message that you included in looks like this is related your theme, Layout2.0.
I have a similar problem with one type of theme (expandable full width artisteer) however only in the backend, when i enter the widget area
a have to scroll down and across to find anything however it all works. this is the warning i get.
Cannot use a scalar value as an array in /var/www/vhosts/******/httpdocs/wp-content/themes/****_****/core/widgets.php on line 16
Here is line (16) $controls[‘params’][‘id’]=$id;
gratefull for any help.