Torque wrench settings for fitting carbon-railed saddle.

It's best you contact Selle for their ESSE torque recommendations. What one mfg recommends for their saddle torque may not apply to another mfg, as carbon layup may differ, with each setting their own recommended torque setting/s.

I know it's not the same manufacturer but Specialized say a max of 9Nm for vertical-load and 13.5Nm for side-load clamps for their saddles with carbon rails.  The main thing is you must use a clamp specifically designed for 7x9mm oval rails and not one for the 7mm rounds ones. I think Selle are 7x9mm oval for carbon rails as well and they say 10-12Nm max. 

http://service.specialized.com/collateral/ownersguide/new/assets/pdf/Saddle---Carbon-Rail-Saddle.pdf

I've got a couple of the Specialized CG-R posts with carbon railed Toupe saddles and I found I had to go to the full 13.5Nm on the side-load clamp to stop the saddle tipping back. 

I set my torque wrench at 6nm, my saddle has not slipped, I am not sure if different seat post fittings require different torque settings, but  why not try 6 and take it for a test ride, if it slips try 7nm, I also applied some carbon paste to the mounting points