I have a Norstar Modular ICS that was running with 2.0 software. For testing purposes, I installed 4.1 software cartridge. Then I reinstalled the 2.0 software cartridge back into the system and now it won't work. All the lights just keep flashing. Will it no longer accept the 2.0 software or is there some way to reset the system. I need the 2.0 software to work again on the ksu. Thanks, Dave 