I have same problem.
PHP version 5.3.x
WordPress 3.4.2
1. I think that it is usial problem for this plugin, try to find “PHP Warning: Parameter 1 to wpdb::escape_by_ref() expected to be a reference” in google…
2. All method in db-module, pass parameters by value (get_row, …) but
function escape_by_ref( &$string )
by reference!
