@PhilipDAth As far as I know the list of supported Switches in the doc is accurate today. There are plans to bring more functionality to the C9300-M. Not sure if it will come to the MS130 family.
As for how SecurePort looks in dashboard. When a switchport has successfully authenticated a Meraki AP it will show a Wi-Fi bars icon on the port. If it fails to auth the AP the port still shows the Wi-Fi icon, but the port would be red. I don't recall if there's a state in which it would be amber. I'm not finding any failing ports in my searching to confirm.
Clicking on the switchport will show you that it's been authenticated by a SecurePort profile.
And clicking on the config comparisons link will show more detail.
I agree with you that adding screenshots like this to the doc might be helpful. Thanks for the suggestion. I'll forward it along to the doc folks.