Hi David,
I use the Edirol UA-25ex with a Macbook myself (though I have Snow Leopard, not Mountain Lion), had some issues getting it to work properly (like you, Advance mode didn't work) but the drivers are available from Roland's support website. I can't post the url 'cos I'm a new member myself but just do a search for the Edirol UA-25 and go to the 'Downloads' tab. Hope this helps!