1. It's not possible with the advanced fields option, it only works with the custom fields. However you can do a quick hack to achieve this. Open up the plugins/ajax-search-pro/includes/search_content.class.php file and go to line 345. That should be an empty line. Put these lines there:
$_cats = get_the_category( $v->id ); if (isset($_cats)) $r->title = $_cats->name.' - '.$r->title;
You should then see the first assigned category name to each post.
3. Not yet. The plugin uses a non-HTML5 placeholder for older mobile support, but it will get removed and replaced with a HTML5 placeholder in the next version, so this issue will disappear soon.Best,
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