I just sent you an email with some things to check.
I have created new Ad (https://www.adplugg.com/apusers/ad/ads/17991)
But it is not getting displayed. My index.html source is below:
<html><head><script>
(function(ac) {
var d = document, s = 'script', id = 'adplugg-adjs';
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = '//www.adplugg.com/apusers/serve/' + ac + '/js/1.1/ad.js';
fjs.parentNode.insertBefore(js, fjs);
}('A48210063'));
</script>
</head><body><div class="adplugg-tag"></div></body></html>