Thanks. I can see it says "edited" next to the ones I make changes to - very useful. The value became 255.
I don't know offhand, and I'm not near my layout computer to check, but all you have to do is select that option without writing it to the decoder, then go to the CV pane and sort it to get the changed value(s) at the top of the list.
I'm looking at editing details on functions for a Tsunami2 decoder. I see CV 1.257 controls the function assigned to the headlight, with a default value of "0" resulting in F0 controlling the headlight. JMRI allows you to reassign, and allows you to choose F0-F28 and "disabled".
If I select "disabled", what value gets assigned to CV 1.257?