I have replaced metal rails with plastic insulated rails (Atlas) at both ends of a reverse loop. I installed an Atlas #210 TWIN (designed for isolating loops and reverse loops) and followed the wiring diagram on the reverse side of the packet.  There is power arriving at the left hand (from transformer) terminals of the #210, but none is then conveyed to either the main line track terminal (the left switch) or the reverse loop track terminal (right switch), regardless of what position the switches are in.  I suspect the Atlas #210 is at fault.  Any suggestions? 
                                                            David