[Plugin: Multi-level Navigation Plugin] Menu not working on IE

I upgraded my plugin a few weeks ago to 2.3.3. It crashed all of my custom HTML that I was using for my menu bar. After repairing it to what seemed just fine for me (a Firefox user), I come to learn, weeks later, that the menu is totally messed up on Internet Explorer. PLEASE someone, tell me how to fix this, when it looks fine to me on Firefox.

http://wordpress.org/extend/plugins/multi-level-navigation-plugin/