no, onProcessTrigger works, the issue is the number of parameters. Fscript pass all parameters to the scripting host. That's not a problem with javascript that is very forgivable about the number of parameters given. VBScript, ruby, etc... expect the exact correct number of parameters.
With recent FARR defining function onProcessTrigger(path, caption, groupname, pluginid,thispluginid,score,entrytype,voidp) will work all the time. Depending of the features of the language we could get full compatibility by defining a function that allow for extra parameters, or overload the function with one of the same name with a different set of parameters.