Can you adjust the CSS z-index of your menubar? In our autocomplete.css you can see Z-INDEX: 999, so you could adjust your menubar to less than 999, or you can add a style rule to your page to bring ours up;
<style>
.sew_ac_results {
Z-INDEX: 999999 !important;
}
</style>
I would't modify autocomplete.css however as that will be overwritten on next upgrade.
Jim
-your feedback is helpful to other users, thank you!