Hi!
You will need a small custom script to do the redirection, when it detects 1 result only.
Try putting this into the functions.php file in your active theme directory:
add_action('wp_footer', 'asl_redirect_on_single');
function asl_redirect_on_single() {
?>
<script>
jQuery(function($) {
$( document ).ajaxComplete(function( event, xhr, settings ) {
if (
typeof settings.data === 'string' &&
settings.data.indexOf('=ajaxsearchlite_search') > -1
) {
var $xhr = $.parseHTML(xhr.responseText);
if ( $('a.asl_res_url', $xhr).length == 1 ) {
$('.wpdreams_asl_results').css('display', 'none');
window.location = $('a.asl_res_url', $xhr).attr('href');
}
}
});
});
</script>
<?php
}
Make sure to clear all the cache layers you have to make this code effective. I hope this helps!