Many complain that chain beats up the deck. Place heavy duty non-skid from the roller to windlass.
I've seen all sorts of lashings holding anchors while underway. A simple pin through the chain works very well and is FAST to release. Mine is home-made from 3/16-inch aluminum, but I believe you can buy them. I would not call this a chain lock - it won't take the strain - but it works better with mixed chain/fiber rodes than available chain locks because it is out of the way when open and permits easy man-hauling when needed. With a fiber rode you snub the rode on a cleat, anyway.
In my case, I always use a bridle and the rode is not loaded. With a catamaran the rode would suffer serious abuse and chafe due to exiting the the bow roller at a 40-60 degree angle. To protect the bridle I use 2-inch tubular climbing webbing (http://www.rei.com/product/472049) where it crosses the bow chock.
In the picture we have stopped for a swim in fine weather. In serious weather or when we leave the boat for a time, the rode would be cleated-off, as a back-up.