I'm really having a hard time getting a basic signalling setup operational. Without going into a bunch of detail, I thought I'd post an example that is confusing me. The attached screenshot shows the Midwestern Branch during session edit. Can someone tell me why the signal is showing yellow and not red?
Even more mystifying is if I move the oncoming loco closer to the signal, it turns green.
Even more mystifying is if I move the oncoming loco closer to the signal, it turns green.

