I have some decoders in dummy cars to control lights etc.in most cases these are standard decoders with just the motor removed, no problem programming these with Bachmann or Hornby but with DCC-EX I have to fit a 100ohm resistor across the motor terminals, again similar with function only decoders they program with commercial controllers but not with DCC-EX but there are no motor terminals to put a resistor across so cannot get them working under DCC-EX