Enable menu to open upwards using slideUp?

[karks88]

I'm trying to use SlickNav in a footer menu that opens upwards (as opposed to the default downwards).

I've changed the jQuery slideDown to slideUp on this line, but no luck in getting it to work:
if (settings.animations === 'jquery') { el.stop(true,true).slideUp(duration, settings.easingOpen, function(){ afterOpen(trigger, parent); });

Has anyone successfully done this?