Sorry I always have to go confirm the fw version, which I did but then forgot to fix my title. Its 125
I cannot be certain of when this started, but I have a button tied to button controller that I often use the activate the kitchen lights (via the activator) in the AM. I tried to use it last night when I forgot something after shutting down, but did not work, and did not work again this morning. That's when I decided to investigate it. Possibly has not been working for longer but if the SO gets downstairs first I don't know if she actually uses the button or some other means to turn the lights on.
Sorry one other thought, is it possibly having an issue because of the unchecked Act for the one light? Is that the 'null' it is complaining about? I have another RL with an activator tied to the same button and that one works fine. It has similar but not identical settings, it does not have anything unchecked and does not use modes. I could give you a screenshot of that one also if it would help.