I saw a sign on the start of the clockwise loop on Tuesday that road is closed at some point ahead - not sure if this means you can still get round on a bike but might be wise to check.
I rode the Cockayne loop a couple of months back, the "road closed" sign was there at that time. There is (or was at the time) a minor landslip in the gated section - easily passable on the bike. That was then, so there's no guarantee that things haven't changed...
It's fine. I rode it a few days ago and it's all rideable. The signs put cars off too so it's nice and quiet. There's a big pothole on the bridge right at the end point though which may get hidden by water if it's raining.