My take on all this:
I am a fan of Joseph Jenkins, the Humanure author. Unless you have a definite need to separate urine from faeces (the only one I can think of is separate application to a new compost pile ala' Steve Solomon), I would do as Jenkins suggests and put urine and faeces together, covering the result with a generous carbonaceous cover material.
All this angst for separating urine seems to be unnecessary...
