Nice tutorial Aaron, I was looking for some information about state of a offline device but couldn’t find anything, that’s how i stumble on this topic. The information I was looking was not here either, but I figured out with trial and error on my 3D floor plan dash.
When one of your devices gets offline by removing it or just because of a failure, you get a broken image over your whole floor plan and that looks ugly since it covers whole 3D plan.
To fix that you need to add an ‘unavailable’ state in your code.
For example:
state_image:
"on": /local/floorplan/kitchen_on.png
"off": /local/floorplan/transparent.png
"unavailable": /local/floorplan/transparent.png
It is up to you if you want to add in your first post.
Now I am looking for curtain switch states, so I can play with closed and open curtains/roller shutters in my plans.