The CGI smpwservicescgi.exe is not found in the Web Agent directory.
Is it still working and supported with the 12.52.xx version of Web Agents?
No, this CGI has been removed from version 12.52.xx.
Even if it was present in the older version of Web Agent, it was deprecated and it's not recommended to use it due to some vulnerabilities.
As such, run the smpwservices.fcc instead, which is the default password service.