Your comments
You should be able to see currently connected VPN users through the regular monitor > client view. You just need to filter by the VPN subnet.
Good idea. I would add CPU and RAM use as well.
True that it could be easier, but it is not too hard to do: https://kb.meraki.com/knowledge_base/creating-a-wireless-guest-vlan-on-the-z1-teleworker-gateway-or-mx60w--security-appliance
Here is a direct link to the Meraki licensing FAQ: https://docs.meraki.com/display/kb/Meraki+Licensing+FAQ
Yes, I discovered that too and it is documented here that all MX systems within an organization must use the same license. https://docs.meraki.com/display/MX/Licensing
Customer support service by UserEcho
The new VPN status view available now does show 3rd party up/down VPN status as well as latency and usage.