When running mootools sortables, when dragging the cloned element around sometimes the cloned element is offset from the mouse pointer. There is a simple method to avoid this. See the enclosing container to position relative. Like so
<ul style=”position:relative”>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
</ul>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
<li>sortable</li>
</ul>
and that’s it.