The directions on the new battery contemplate the use of both kinds of chargers. Instructions say charge 1-3 hours in a smart battery charger or 7-8 hours in a regular battery charger. This is for the first charge. Then it says do not let it discharge completely and make sure to recharge every thirty days if it is not in use. So it has been completely charged once now (8 hrs on the dumb charger) and works fine in my tools.

Still stumped about the red light.