They fixed the problem of cook off and i believe they have made it water proof. The bullet is no longer protruding out of the propellant, but rather inside the propellant.
The new caseless has been tested to increase the cook-off temperature an additional 200 degrees celsius to the gun.
So it will take more temperature for a gun with caseless to cook-off than a brass cased bullet gun.
The caseless as made so it only will ignit when the primer is struck. So it will only set of when fired from a gun. So its not too much of a problem, unless u leave it in the flame for a while.
The propellant is cover wtih a water repellant coating that makes the caseless water proof.