As I understand it,
RJK set up Creations Unlimited to publish his own D&D adventures following the general departure of the originating authors from TSR. He first published Garden of the Plantmaster, an original level from the original Castle Greyhawk, and then the Zayene modules, again from the ongoing campaigns
RJK ran. When he closed Creations Unlimited he sold all his stock to
NKG (hense their abundence of these things), and sometime this millenium sold the rights to republish the Zayene modules to NG. NG had to redraft the modules to comply with the
d20 license, and to work with 3/3.5E, but as far as I'm aware,
RJK wasn't involved in the rewrite/editting of the NG product. Same goes for City of Brass.
This week I've been mostly eating . . . The white ones with the little red flecks in them.