Well, now I can get the replays to work. The issue I am having currently is that the saved replays do not have the shader applied. If you hit escape in the session and select replay from that menu (the legacy Resume/Back to Pits/Replay/Exit pop up), the race will replay and the day to night shading progresses as in the race. If I select the replay in "content" then the race does replay, but everything appears as mid-day - no change in lighting, no clouds/weather effects that were appearing in the race and the replay in-session. I'm sure I have something checked wrong somewhere, but as of right now I don't know why my saved replays do not have Sol applied.
FWIW I have Ultra (64 Hz) checked for quality. That hasn't been a problem before, and it's not when replaying in the session, just on saved content.