There is an issue with speed limits with Santa Fe on Cajon Pass. After a few runs in the Dash 8 I have noticed that not all speed limit changes are shown on the HUD, and when they do, they do not match the trackside signage for freight trains. This makes it impossible to drive safely and receive maximum points, on Cajon Pass of all routes, where careful speed management is required. As its a pretty fundamental aspect of the content I hope to see a fix very soon.
Can confirm as well! Happens on this route with both stock from the Santa Fe Gameplay pack. Also, I personally noticed this same issue happens on New York - Trenton around Metuchen with the Metroliner Cab Car. Seems very reproducible on pre-TSW4 built routes. GIF below for reference: