I am unable to ping appliances or other IP's from my devices. I have multiple MX64's and MX85's and its not working on any of them. I also tried to start a ticket but it keeps giving me errors when submitting the ticket.
There is a dashboard issue https://status.meraki.net/ while the alert says only logins, I'm seeing similar issues as you plus config changes seem to take, but can't claim orders/licenses or add new devices to networks, etc.
The MX device is not registered to meraki dashdoared. Default deny for inbound ICMP to WAN internet port. Once registered, the default config in dashboard with "allow any" for ICMP is pushed to the device.