I have both the Edinburgh-Glasgow Route add-on DLC and the Edinburgh-Glasgow: Engineering Express DLC installed. When in the scenario "Spring Morning", the dellner adapter appears and functions as expected. The issue comes when I spawn a Class 66 in Freemode and try to use the emergency adapter coupler. The only options for coupling are the hook & chain and buckeye couplers. I find that in the "Spring Morning" scenario, it can be a little finnicky to get the option to attach the dellner coupler to appear, but in freeroam the option never appears. I have tried with the DRS, EWS, DBS, ONE, and TCC Class 66 variants available to me in the spawn train menu. I can go into formation designer and create a Class 66 + Class 385 formation. However, the coupler doesn't appear, but the train can be driven like normal. I have tried verifying my game cache in Steam, but this hasn't fixed the problem. Has anyone come across this issue before? Is there something obvious I'm missing to use the dellner coupler in free roam?