If you have a decent piece of complex vector artwork and need to extract an outer contour either get a mimaki and get finecut (sorry I had to!), or take your artwork (again vector stuff only), group it (expand everything too) and place it over a filled box. Select both the box and the grouped artwork and use the divide filter. Now select the box with the point select tool (white arrow, not black) switch to the object select tool (black arrow) but don't click on anything, now cut and then paste in front. This will cut the box away from the object and when you paste it down, it will have a vector path removed delineating the border of your artwork. Select the new box and go to release compound path. Offset the path with the offset path option if you need a border, likewise, if you want a bleed, duplicate the path behind the objects and offset it with the color you want for the bleed leaving the non-offset path as your cut line.
