New roundabout at monks farm is dangerous with one lane closed

Running up to the new roundabout travelling west from Brighton the left lane is closed but as you enter the roundabout the right lane is closed off. This means you have to swerve onto the left lane otherwise traffic on the right will drive straight into you. This isn't obvious on approach at all. As an advanced driving instructor and instructor trainer in my opinion this situation can and probably will cause serious injury if not dealt with. Most vehicles on the right lane will assume that cars on the left will move over but the cones will stop them thinking this is something they can do. This needs action! What's worse is there is now a large cone in the left hand lane on the actual roundabout which makes it look impossible to move into the left lane!