Hopefully my memory is not playing tricks on me but if I remember correctly, soon after the MetaStock forum was created, the Team and I thought that we needed a sort of open source project. It was called - The Forum DLL and the Copyright belongs to "The MetaStock Forum Crew" :)
The power pivot plugin was maybe the most annoying one to support as its value was not in the systems it offered but in some of the functions it used. The most interesting one was the latch function. So the first function I programmed for the Forum.dll was a type of latch function which was tweaked and improved on by the rest of the community.
The screenshot is of a review by Roy Larsen from www.metastocktips.co.nz back in 2006, this plugin is still being used as of 2011.
The help file, which show the details of all 15 functions is included in the zip file, also keep in mind that this is still available on http://forum.equis.com