Popp Z-Wave Smoke Detector & Siren - problems

Hi

I’ve got a few Smoke Alarm and sirens, powered with the purchased mains adapters.

(It seems I must also have batteries installed as a backup, but in fact the batteries seem to drain fast anyway).

Nevertheless I am confused with what is going on with the app.

As can be seen in the screenshot below, in some of the devices the icons are white, some grey, some grey with an exclamation mark. It’s not clear to me what is meant by each.

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If I press and hold the white one, I get an icon of a power button illuminated green.

What does that mean?

Does it mean the siren is supposed to be sounding or simply that the device is enabled?

If I do the same for a grey icon the alarm siren starts, and won’t go off until I turn it off again.

(Also left a message on @MarcoRuiter’s app’s github issues page, but hoping somebody here might know the answers)

Can anybody help with this? (no response from the developer)