So you came here looking for documentation for MooPlug and here it is!
There is the Functions List which explains every MooPlug function, what it does, what parameters it accepts and what it should output. As well as an example or two just to show you how it's done. There is a sample FileMaker file included with the MooPlug download which shows a real working example off each and every function, so once you've downloaded it just take a look in ScriptMaker and see how each script works.
That's all well and good, but what happens if you're having some problems getting MooPlug to work and it keeps returning different error codes which don't mean a thing!? Well that's when you need to look at the Error Descriptions page, which lists every possible MooPlug error code, along with a nice human-readable description of the problem which should help you get sorted!
As well as having the error codes on this website, they are included within MooPlug itself. You can use the Moo_ErrorDetail function to return the exact same text you will find on the Error Descriptions page, all you have todo is pass it the error code in question.