I think I found a ‘bug’ in Ajax Search Pro for WordPress, file hooks.php last line reads:
add_action('wp_print_styles', 'search_stylesheets');
should read:
add_action('wp_enqueue_scripts', 'search_stylesheets');
Why? According to http://codex.wordpress.org/Plugin_API/Action_Reference/wp_print_styles: Since WordPress 3.3 wp_print_styles should not be used to enqueue styles or scripts.
Why is this a problem? If, like me, someone wants to edit the stylesheet by removing it and enqueuing our own, we can’t. Maybe you could make this little change for the next release? Otherwise I have to be careful about when I update that the updates don’t remove what I have done.