I posted this earlier on Greytalk in response to something Ubiquitious said, and I thought it important enought to re-post on Canonfire. But it begs the question, on how difficult it is to convert Greyhawk to the HackMaster(TM) system, and is it worth it?
By: Tracy (firstname.lastname@example.org)
(Used with Permission. Do not repost without obtaining prior permission from the author.)
One thing about HackMaster(TM) is it assumes muchly that everyone will play in the "Garweese Wurld" and therefore all the hooks to the play setting lead to it, such as Gawds and Garweese specific races and beasts.
According to the HackMaster(TM) Player's Handbook on page 13, removing such 'hooks' from the rules and replacing them with Greyhawk specific ones could be viewed by some as being a "rogue-GM" by the HackMaster Player's Association.
So if you're willing to overcome such a stigma, I'd suggest just removing "Gnome Titans" from any version of GreyHack if you want to stay within a canonical Greyhawk milieu.
Justin Thyme Productions