Are you powering your switches with DC power?
They technically function on DC power- the motor will switch and anti-derailing functions, but the RSC lights function needs AC to make both polarities.- Hence why you would get one color but not the other.
Your circuit for the LEDs looks correct- which is why I suspect you might be caught in the DC power source problem- which I had not seen a warning about in the manual but I knew about from testing and the occasional starter set customer at the hobby shop complaining when they use the DC wall power that comes with Lionchief sets.
