Please check host server is running properly and check if the host server is behind firewall. If the server is behind firewall and check port 445 and 135 is accessible and if not accessible, then open the port by configuring the firewall.
Please check Dot Net platform is installed in your system. Run the utility available in the bin directory, DotNetUtilities.exe , It will tell you the Dot Net version. If Dot Net platform is not available in the system, download the platform. Please see the software requirements page for downloading the platform.
In Host server, If at all, CPU utilized or Memory used value exceeds the configured threshold values, the tool will then show the alert on the Dashboard to intimate status.
The values of SharePoint Snapshot are "NA", if the SharePoint Server Environment is not installed in the connected host server. So connect to host where SharePoint Server is installed.
The SharePoint Site Response time value "Zero" represents, the site is down or the specified site is not available during the site request.