I am trying to use the FireWire Card Tester application that came with Apple's original FireWire PCI card. It always tells me that the FireWire card is not responding even when it seems to be working. Why is this?

The FireWire Card Tester application works only with the original Apple FireWire PCI card which it came with. It will not recognize third-party FireWire cards or the built-in FireWire on Apple's later computers.