Are you still having issues connecting to Arc? If so, please fill out @Maarten_Duits’ questions
Thank you for your patience while we’ve diligently worked to reach every request for support with port forwarding. The diagnostics you’ve provided suggest that UPnP is not properly configured on your router.
Please first try the following steps:
Try to enable UPnP/NATPMP in the web administration interface for the router directly upstream from your Core
Try to manually open the port in your router’s port forwarding configuration
Make sure the IP/Port matches the Port listed in Roon → Settings → ARC
Check for any VPNs or Firewalls that might be interfering