There doesnt appear to be any powershell suport. I see support for scripts like VBS via batch files, but direct support of powershell would be perfect. Even indirect support via a batch file calling a powershell script would also work.
I have tested this out using a batch file calling a powershell script and the service test just reads Testing… please wait.
Powershell is so much easier to script and would make custom monitors so much easier for windows servers, especiall custom WMI scripts.