Currently, YAK causes jQuery Tools to be loaded on all WP admin pages, thereby breaking an important Drag & Drop functionality in NextGEN gallery.
I have temporarily solved this problem by replacing the line 1420 in yak-for-wordpress.php, which was
$url = $_SERVER["REQUEST_URI"];
if (yak_str_contains($url, 'yak'))
wp_enqueue_script('jquery-tools', "$yakurl/jquery.tools.min.js", null, null);
One can certainly do better, i.e. do the same for other files that need to be loaded only when visiting the YAK settings pages, or provide a better way of checking whether we are on the YAK settings page.
Note that I also changed the wp_enqueue_script line, because with the old line, WordPress would append its version string to the jquery.tools.min.js file, such that it could not be found anymore.