When adding the exception for SvcHost.exe, I get the following message.
Windows services have been restricted with rules that allow expected behavior only. Rules that specify host processes, such as svchost.exe, might not work as expected because they can conflict with Windows service-hardening rules.
Are you sure that you want to create a rule referencing this process?
Here's bit of info on Service-Hardening.
http://sourcedaddy.com/windows-7/understanding-windows-service-hardening.html