DbgView for watching trace messages live on FileMaker Server
As you see MBS FileMaker Plugin on Server always prints this welcome line including version, platform, 32/64bit, which FileMaker process and the version of the FileMaker SDK reported by the loading FileMaker application.
If you use MBS("Trace") without a file path, you will see all calls to plugin functions in the log, too. This is very handy to have a live view on what's going on with the plugin. If you set the option to trace only errors with Trace.ErrorsOnly, you only see the calls which return an error message.