If they seem under developed, that points to your temps being low over the average. Make sure that any thermometers you are using are checked for accuracy, (and I strongly suggest having 2 independent therms in bator). If you are using the 9300, they are notorious for the gages being off and most users have to set the bator 1-3 degrees higher to get the needed temps inside. Never trust bator gages unless they've been checked.
Personally if you are home to monior frequently, I would run dry with no water until I heard a cheeping inside the egg or saw an external pip and I would hatch upright in cut down cartons if the air cells are significantly small. If the development is behind you can probably get the air cells significantly larger before there is any action of hatching.