Trouble inputting microtones in Dorico 4

I’m trying to use microtonal accidentals in a Dorico 4 score. I’ve added an atonal key signature, and I went to the key signature panel on the right side, in Write mode. I selected Equal Temperament (24-EDO). However, when I start note entry, Dorico reverts to 12-EDO. If I select a note, select 24-EDO in the panel, and click on a microtonal accidental, it does not show up, and it reverts to 12-EDO.

What am I missing here?

You need to select the tonality system first, then insert the key signature. That’s what puts the key signature in that system.

That worked, thanks!