So I went Googling again and found this:
I followed the instructions of manually adding the Adobe PDF as a printer. When I open Acrobat, it does see that printer. Separations is an option. But after setting everything up, when I hit "Print", the "Printer" pops up and quickly disappears and nothing happens.
I can not be the only guy who is trying to print separations from Acrobat on a post-Snow Leopard Mac for screen printing....
This is absurd... I would like to thank Apple for deciding what my workflow should be and making it impossible to do my job.