Dome Siren Device Present in RM4, disappears from WebCoRE

I repeatedly add a connected Dome Siren to WebCoRE Settings, but as soon as I try to create an action with it, it's gone from the device list.

It's present for Rule Machine, but it won't "stick" when added to WebCoRE.

I really need a chime generator in WebCoRE. Pls Help!

Can you show logs and settings?

You might want a private message

Thanks you helped me track it down. I wasn't saving the configuration properly (Next > Done).

Now I have another elementary question.

I see examples of a SET command in Smartthings' webcore, but I can't seem to find any way to perform math operations in HE webcore.

How can I do "Set RefTemp = RefTemp + 10"?

Never mind answered my own question. Wasn't that easy?