Rollover menu problems

Hi. I’m a newbie, and I’ve been playing around with the CSS of minimatica to pretty good results, but can anyone tell me why I can’t get the submenus on my navigation to stay visible? It’s driving me nuts. It seems to work the first time I land on the page, but any subsequent visits to the rollover doesn’t work. Is it a z-index issue?

My site is here:

http://www.eastvillageart/staging

Thanks in advance!